1CSV_XS(3)             User Contributed Perl Documentation            CSV_XS(3)
2
3
4

NAME

6       Text::CSV_XS - comma-separated values manipulation routines
7

SYNOPSIS

9        # Functional interface
10        use Text::CSV_XS qw( csv );
11
12        # Read whole file in memory
13        my $aoa = csv (in => "data.csv");    # as array of array
14        my $aoh = csv (in => "data.csv",
15                       headers => "auto");   # as array of hash
16
17        # Write array of arrays as csv file
18        csv (in => $aoa, out => "file.csv", sep_char=> ";");
19
20        # Only show lines where "code" is odd
21        csv (in => "data.csv", filter => { code => sub { $_ % 2 }});
22
23
24        # Object interface
25        use Text::CSV_XS;
26
27        my @rows;
28        # Read/parse CSV
29        my $csv = Text::CSV_XS->new ({ binary => 1, auto_diag => 1 });
30        open my $fh, "<:encoding(utf8)", "test.csv" or die "test.csv: $!";
31        while (my $row = $csv->getline ($fh)) {
32            $row->[2] =~ m/pattern/ or next; # 3rd field should match
33            push @rows, $row;
34            }
35        close $fh;
36
37        # and write as CSV
38        open $fh, ">:encoding(utf8)", "new.csv" or die "new.csv: $!";
39        $csv->say ($fh, $_) for @rows;
40        close $fh or die "new.csv: $!";
41

DESCRIPTION

43       Text::CSV_XS  provides facilities for the composition  and
44       decomposition of comma-separated values.  An instance of the
45       Text::CSV_XS class will combine fields into a "CSV" string and parse a
46       "CSV" string into fields.
47
48       The module accepts either strings or files as input  and support the
49       use of user-specified characters for delimiters, separators, and
50       escapes.
51
52   Embedded newlines
53       Important Note:  The default behavior is to accept only ASCII
54       characters in the range from 0x20 (space) to 0x7E (tilde).   This means
55       that the fields can not contain newlines. If your data contains
56       newlines embedded in fields, or characters above 0x7E (tilde), or
57       binary data, you must set "binary => 1" in the call to "new". To cover
58       the widest range of parsing options, you will always want to set
59       binary.
60
61       But you still have the problem  that you have to pass a correct line to
62       the "parse" method, which is more complicated from the usual point of
63       usage:
64
65        my $csv = Text::CSV_XS->new ({ binary => 1, eol => $/ });
66        while (<>) {           #  WRONG!
67            $csv->parse ($_);
68            my @fields = $csv->fields ();
69            }
70
71       this will break, as the "while" might read broken lines:  it does not
72       care about the quoting. If you need to support embedded newlines,  the
73       way to go is to  not  pass "eol" in the parser  (it accepts "\n", "\r",
74       and "\r\n" by default) and then
75
76        my $csv = Text::CSV_XS->new ({ binary => 1 });
77        open my $fh, "<", $file or die "$file: $!";
78        while (my $row = $csv->getline ($fh)) {
79            my @fields = @$row;
80            }
81
82       The old(er) way of using global file handles is still supported
83
84        while (my $row = $csv->getline (*ARGV)) { ... }
85
86   Unicode
87       Unicode is only tested to work with perl-5.8.2 and up.
88
89       See also "BOM".
90
91       The simplest way to ensure the correct encoding is used for  in- and
92       output is by either setting layers on the filehandles, or setting the
93       "encoding" argument for "csv".
94
95        open my $fh, "<:encoding(UTF-8)", "in.csv"  or die "in.csv: $!";
96       or
97        my $aoa = csv (in => "in.csv",     encoding => "UTF-8");
98
99        open my $fh, ">:encoding(UTF-8)", "out.csv" or die "out.csv: $!";
100       or
101        csv (in => $aoa, out => "out.csv", encoding => "UTF-8");
102
103       On parsing (both for  "getline" and  "parse"),  if the source is marked
104       being UTF8, then all fields that are marked binary will also be marked
105       UTF8.
106
107       On combining ("print"  and  "combine"):  if any of the combining fields
108       was marked UTF8, the resulting string will be marked as UTF8.  Note
109       however that all fields  before  the first field marked UTF8 and
110       contained 8-bit characters that were not upgraded to UTF8,  these will
111       be  "bytes"  in the resulting string too, possibly causing unexpected
112       errors.  If you pass data of different encoding,  or you don't know if
113       there is  different  encoding, force it to be upgraded before you pass
114       them on:
115
116        $csv->print ($fh, [ map { utf8::upgrade (my $x = $_); $x } @data ]);
117
118       For complete control over encoding, please use Text::CSV::Encoded:
119
120        use Text::CSV::Encoded;
121        my $csv = Text::CSV::Encoded->new ({
122            encoding_in  => "iso-8859-1", # the encoding comes into   Perl
123            encoding_out => "cp1252",     # the encoding comes out of Perl
124            });
125
126        $csv = Text::CSV::Encoded->new ({ encoding  => "utf8" });
127        # combine () and print () accept *literally* utf8 encoded data
128        # parse () and getline () return *literally* utf8 encoded data
129
130        $csv = Text::CSV::Encoded->new ({ encoding  => undef }); # default
131        # combine () and print () accept UTF8 marked data
132        # parse () and getline () return UTF8 marked data
133
134   BOM
135       BOM  (or Byte Order Mark)  handling is available only inside the
136       "header" method.   This method supports the following encodings:
137       "utf-8", "utf-1", "utf-32be", "utf-32le", "utf-16be", "utf-16le",
138       "utf-ebcdic", "scsu", "bocu-1", and "gb-18030". See Wikipedia
139       <https://en.wikipedia.org/wiki/Byte_order_mark>.
140
141       If a file has a BOM, the easiest way to deal with that is
142
143        my $aoh = csv (in => $file, detect_bom => 1);
144
145       All records will be encoded based on the detected BOM.
146
147       This implies a call to the  "header"  method,  which defaults to also
148       set the "column_names". So this is not the same as
149
150        my $aoh = csv (in => $file, headers => "auto");
151
152       which only reads the first record to set  "column_names"  but ignores
153       any meaning of possible present BOM.
154

SPECIFICATION

156       While no formal specification for CSV exists, RFC 4180
157       <https://tools.ietf.org/html/rfc4180> (1) describes the common format
158       and establishes  "text/csv" as the MIME type registered with the IANA.
159       RFC 7111 <http://tools.ietf.org/html/rfc7111> (2) adds fragments to
160       CSV.
161
162       Many informal documents exist that describe the "CSV" format.   "How
163       To: The Comma Separated Value (CSV) File Format"
164       <http://www.creativyst.com/Doc/Articles/CSV/CSV01.htm> (3)  provides an
165       overview of the  "CSV"  format in the most widely used applications and
166       explains how it can best be used and supported.
167
168        1) https://tools.ietf.org/html/rfc4180
169        2) https://tools.ietf.org/html/rfc7111
170        3) http://www.creativyst.com/Doc/Articles/CSV/CSV01.htm
171
172       The basic rules are as follows:
173
174       CSV  is a delimited data format that has fields/columns separated by
175       the comma character and records/rows separated by newlines. Fields that
176       contain a special character (comma, newline, or double quote),  must be
177       enclosed in double quotes. However, if a line contains a single entry
178       that is the empty string, it may be enclosed in double quotes.  If a
179       field's value contains a double quote character it is escaped by
180       placing another double quote character next to it. The "CSV" file
181       format does not require a specific character encoding, byte order, or
182       line terminator format.
183
184       • Each record is a single line ended by a line feed  (ASCII/"LF"=0x0A)
185         or a carriage return and line feed pair (ASCII/"CRLF"="0x0D 0x0A"),
186         however, line-breaks may be embedded.
187
188       • Fields are separated by commas.
189
190       • Allowable characters within a "CSV" field include 0x09 ("TAB") and
191         the inclusive range of 0x20 (space) through 0x7E (tilde).  In binary
192         mode all characters are accepted, at least in quoted fields.
193
194       • A field within  "CSV"  must be surrounded by  double-quotes to
195         contain  a separator character (comma).
196
197       Though this is the most clear and restrictive definition,  Text::CSV_XS
198       is way more liberal than this, and allows extension:
199
200       • Line termination by a single carriage return is accepted by default
201
202       • The separation-, escape-, and escape- characters can be any ASCII
203         character in the range from  0x20 (space) to  0x7E (tilde).
204         Characters outside this range may or may not work as expected.
205         Multibyte characters, like UTF "U+060C" (ARABIC COMMA),   "U+FF0C"
206         (FULLWIDTH COMMA),  "U+241B" (SYMBOL FOR ESCAPE), "U+2424" (SYMBOL
207         FOR NEWLINE), "U+FF02" (FULLWIDTH QUOTATION MARK), and "U+201C" (LEFT
208         DOUBLE QUOTATION MARK) (to give some examples of what might look
209         promising) work for newer versions of perl for "sep_char", and
210         "quote_char" but not for "escape_char".
211
212         If you use perl-5.8.2 or higher these three attributes are
213         utf8-decoded, to increase the likelihood of success. This way
214         "U+00FE" will be allowed as a quote character.
215
216       • A field in  "CSV"  must be surrounded by double-quotes to make an
217         embedded double-quote, represented by a pair of consecutive double-
218         quotes, valid. In binary mode you may additionally use the sequence
219         ""0" for representation of a NULL byte. Using 0x00 in binary mode is
220         just as valid.
221
222       • Several violations of the above specification may be lifted by
223         passing some options as attributes to the object constructor.
224

METHODS

226   version
227       (Class method) Returns the current module version.
228
229   new
230       (Class method) Returns a new instance of class Text::CSV_XS. The
231       attributes are described by the (optional) hash ref "\%attr".
232
233        my $csv = Text::CSV_XS->new ({ attributes ... });
234
235       The following attributes are available:
236
237       eol
238
239        my $csv = Text::CSV_XS->new ({ eol => $/ });
240                  $csv->eol (undef);
241        my $eol = $csv->eol;
242
243       The end-of-line string to add to rows for "print" or the record
244       separator for "getline".
245
246       When not passed in a parser instance,  the default behavior is to
247       accept "\n", "\r", and "\r\n", so it is probably safer to not specify
248       "eol" at all. Passing "undef" or the empty string behave the same.
249
250       When not passed in a generating instance,  records are not terminated
251       at all, so it is probably wise to pass something you expect. A safe
252       choice for "eol" on output is either $/ or "\r\n".
253
254       Common values for "eol" are "\012" ("\n" or Line Feed),  "\015\012"
255       ("\r\n" or Carriage Return, Line Feed),  and "\015"  ("\r" or Carriage
256       Return). The "eol" attribute cannot exceed 7 (ASCII) characters.
257
258       If both $/ and "eol" equal "\015", parsing lines that end on only a
259       Carriage Return without Line Feed, will be "parse"d correct.
260
261       sep_char
262
263        my $csv = Text::CSV_XS->new ({ sep_char => ";" });
264                $csv->sep_char (";");
265        my $c = $csv->sep_char;
266
267       The char used to separate fields, by default a comma. (",").  Limited
268       to a single-byte character, usually in the range from 0x20 (space) to
269       0x7E (tilde). When longer sequences are required, use "sep".
270
271       The separation character can not be equal to the quote character  or to
272       the escape character.
273
274       See also "CAVEATS"
275
276       sep
277
278        my $csv = Text::CSV_XS->new ({ sep => "\N{FULLWIDTH COMMA}" });
279                  $csv->sep (";");
280        my $sep = $csv->sep;
281
282       The chars used to separate fields, by default undefined. Limited to 8
283       bytes.
284
285       When set, overrules "sep_char".  If its length is one byte it acts as
286       an alias to "sep_char".
287
288       See also "CAVEATS"
289
290       quote_char
291
292        my $csv = Text::CSV_XS->new ({ quote_char => "'" });
293                $csv->quote_char (undef);
294        my $c = $csv->quote_char;
295
296       The character to quote fields containing blanks or binary data,  by
297       default the double quote character (""").  A value of undef suppresses
298       quote chars (for simple cases only). Limited to a single-byte
299       character, usually in the range from  0x20 (space) to  0x7E (tilde).
300       When longer sequences are required, use "quote".
301
302       "quote_char" can not be equal to "sep_char".
303
304       quote
305
306        my $csv = Text::CSV_XS->new ({ quote => "\N{FULLWIDTH QUOTATION MARK}" });
307                    $csv->quote ("'");
308        my $quote = $csv->quote;
309
310       The chars used to quote fields, by default undefined. Limited to 8
311       bytes.
312
313       When set, overrules "quote_char". If its length is one byte it acts as
314       an alias to "quote_char".
315
316       This method does not support "undef".  Use "quote_char" to disable
317       quotation.
318
319       See also "CAVEATS"
320
321       escape_char
322
323        my $csv = Text::CSV_XS->new ({ escape_char => "\\" });
324                $csv->escape_char (":");
325        my $c = $csv->escape_char;
326
327       The character to  escape  certain characters inside quoted fields.
328       This is limited to a  single-byte  character,  usually  in the  range
329       from  0x20 (space) to 0x7E (tilde).
330
331       The "escape_char" defaults to being the double-quote mark ("""). In
332       other words the same as the default "quote_char". This means that
333       doubling the quote mark in a field escapes it:
334
335        "foo","bar","Escape ""quote mark"" with two ""quote marks""","baz"
336
337       If  you  change  the   "quote_char"  without  changing  the
338       "escape_char",  the  "escape_char" will still be the double-quote
339       (""").  If instead you want to escape the  "quote_char" by doubling it
340       you will need to also change the  "escape_char"  to be the same as what
341       you have changed the "quote_char" to.
342
343       Setting "escape_char" to <undef> or "" will disable escaping completely
344       and is greatly discouraged. This will also disable "escape_null".
345
346       The escape character can not be equal to the separation character.
347
348       binary
349
350        my $csv = Text::CSV_XS->new ({ binary => 1 });
351                $csv->binary (0);
352        my $f = $csv->binary;
353
354       If this attribute is 1,  you may use binary characters in quoted
355       fields, including line feeds, carriage returns and "NULL" bytes. (The
356       latter could be escaped as ""0".) By default this feature is off.
357
358       If a string is marked UTF8,  "binary" will be turned on automatically
359       when binary characters other than "CR" and "NL" are encountered.   Note
360       that a simple string like "\x{00a0}" might still be binary, but not
361       marked UTF8, so setting "{ binary => 1 }" is still a wise option.
362
363       strict
364
365        my $csv = Text::CSV_XS->new ({ strict => 1 });
366                $csv->strict (0);
367        my $f = $csv->strict;
368
369       If this attribute is set to 1, any row that parses to a different
370       number of fields than the previous row will cause the parser to throw
371       error 2014.
372
373       skip_empty_rows
374
375        my $csv = Text::CSV_XS->new ({ skip_empty_rows => 1 });
376                $csv->skip_empty_rows (0);
377        my $f = $csv->skip_empty_rows;
378
379       If this attribute is set to 1,  any row that has an  "eol" immediately
380       following the start of line will be skipped.  Default behavior is to
381       return one single empty field.
382
383       This attribute is only used in parsing.
384
385       formula_handling
386
387       formula
388
389        my $csv = Text::CSV_XS->new ({ formula => "none" });
390                $csv->formula ("none");
391        my $f = $csv->formula;
392
393       This defines the behavior of fields containing formulas. As formulas
394       are considered dangerous in spreadsheets, this attribute can define an
395       optional action to be taken if a field starts with an equal sign ("=").
396
397       For purpose of code-readability, this can also be written as
398
399        my $csv = Text::CSV_XS->new ({ formula_handling => "none" });
400                $csv->formula_handling ("none");
401        my $f = $csv->formula_handling;
402
403       Possible values for this attribute are
404
405       none
406         Take no specific action. This is the default.
407
408          $csv->formula ("none");
409
410       die
411         Cause the process to "die" whenever a leading "=" is encountered.
412
413          $csv->formula ("die");
414
415       croak
416         Cause the process to "croak" whenever a leading "=" is encountered.
417         (See Carp)
418
419          $csv->formula ("croak");
420
421       diag
422         Report position and content of the field whenever a leading  "=" is
423         found.  The value of the field is unchanged.
424
425          $csv->formula ("diag");
426
427       empty
428         Replace the content of fields that start with a "=" with the empty
429         string.
430
431          $csv->formula ("empty");
432          $csv->formula ("");
433
434       undef
435         Replace the content of fields that start with a "=" with "undef".
436
437          $csv->formula ("undef");
438          $csv->formula (undef);
439
440       a callback
441         Modify the content of fields that start with a  "="  with the return-
442         value of the callback.  The original content of the field is
443         available inside the callback as $_;
444
445          # Replace all formula's with 42
446          $csv->formula (sub { 42; });
447
448          # same as $csv->formula ("empty") but slower
449          $csv->formula (sub { "" });
450
451          # Allow =4+12
452          $csv->formula (sub { s/^=(\d+\+\d+)$/$1/eer });
453
454          # Allow more complex calculations
455          $csv->formula (sub { eval { s{^=([-+*/0-9()]+)$}{$1}ee }; $_ });
456
457       All other values will give a warning and then fallback to "diag".
458
459       decode_utf8
460
461        my $csv = Text::CSV_XS->new ({ decode_utf8 => 1 });
462                $csv->decode_utf8 (0);
463        my $f = $csv->decode_utf8;
464
465       This attributes defaults to TRUE.
466
467       While parsing,  fields that are valid UTF-8, are automatically set to
468       be UTF-8, so that
469
470         $csv->parse ("\xC4\xA8\n");
471
472       results in
473
474         PV("\304\250"\0) [UTF8 "\x{128}"]
475
476       Sometimes it might not be a desired action.  To prevent those upgrades,
477       set this attribute to false, and the result will be
478
479         PV("\304\250"\0)
480
481       auto_diag
482
483        my $csv = Text::CSV_XS->new ({ auto_diag => 1 });
484                $csv->auto_diag (2);
485        my $l = $csv->auto_diag;
486
487       Set this attribute to a number between 1 and 9 causes  "error_diag" to
488       be automatically called in void context upon errors.
489
490       In case of error "2012 - EOF", this call will be void.
491
492       If "auto_diag" is set to a numeric value greater than 1, it will "die"
493       on errors instead of "warn".  If set to anything unrecognized,  it will
494       be silently ignored.
495
496       Future extensions to this feature will include more reliable auto-
497       detection of  "autodie"  being active in the scope of which the error
498       occurred which will increment the value of "auto_diag" with  1 the
499       moment the error is detected.
500
501       diag_verbose
502
503        my $csv = Text::CSV_XS->new ({ diag_verbose => 1 });
504                $csv->diag_verbose (2);
505        my $l = $csv->diag_verbose;
506
507       Set the verbosity of the output triggered by "auto_diag".   Currently
508       only adds the current  input-record-number  (if known)  to the
509       diagnostic output with an indication of the position of the error.
510
511       blank_is_undef
512
513        my $csv = Text::CSV_XS->new ({ blank_is_undef => 1 });
514                $csv->blank_is_undef (0);
515        my $f = $csv->blank_is_undef;
516
517       Under normal circumstances, "CSV" data makes no distinction between
518       quoted- and unquoted empty fields.  These both end up in an empty
519       string field once read, thus
520
521        1,"",," ",2
522
523       is read as
524
525        ("1", "", "", " ", "2")
526
527       When writing  "CSV" files with either  "always_quote" or  "quote_empty"
528       set, the unquoted  empty field is the result of an undefined value.
529       To enable this distinction when  reading "CSV"  data,  the
530       "blank_is_undef"  attribute will cause  unquoted empty fields to be set
531       to "undef", causing the above to be parsed as
532
533        ("1", "", undef, " ", "2")
534
535       Note that this is specifically important when loading  "CSV" fields
536       into a database that allows "NULL" values,  as the perl equivalent for
537       "NULL" is "undef" in DBI land.
538
539       empty_is_undef
540
541        my $csv = Text::CSV_XS->new ({ empty_is_undef => 1 });
542                $csv->empty_is_undef (0);
543        my $f = $csv->empty_is_undef;
544
545       Going one  step  further  than  "blank_is_undef",  this attribute
546       converts all empty fields to "undef", so
547
548        1,"",," ",2
549
550       is read as
551
552        (1, undef, undef, " ", 2)
553
554       Note that this affects only fields that are  originally  empty,  not
555       fields that are empty after stripping allowed whitespace. YMMV.
556
557       allow_whitespace
558
559        my $csv = Text::CSV_XS->new ({ allow_whitespace => 1 });
560                $csv->allow_whitespace (0);
561        my $f = $csv->allow_whitespace;
562
563       When this option is set to true,  the whitespace  ("TAB"'s and
564       "SPACE"'s) surrounding  the  separation character  is removed when
565       parsing.  If either "TAB" or "SPACE" is one of the three characters
566       "sep_char", "quote_char", or "escape_char" it will not be considered
567       whitespace.
568
569       Now lines like:
570
571        1 , "foo" , bar , 3 , zapp
572
573       are parsed as valid "CSV", even though it violates the "CSV" specs.
574
575       Note that  all  whitespace is stripped from both  start and  end of
576       each field.  That would make it  more than a feature to enable parsing
577       bad "CSV" lines, as
578
579        1,   2.0,  3,   ape  , monkey
580
581       will now be parsed as
582
583        ("1", "2.0", "3", "ape", "monkey")
584
585       even if the original line was perfectly acceptable "CSV".
586
587       allow_loose_quotes
588
589        my $csv = Text::CSV_XS->new ({ allow_loose_quotes => 1 });
590                $csv->allow_loose_quotes (0);
591        my $f = $csv->allow_loose_quotes;
592
593       By default, parsing unquoted fields containing "quote_char" characters
594       like
595
596        1,foo "bar" baz,42
597
598       would result in parse error 2034.  Though it is still bad practice to
599       allow this format,  we  cannot  help  the  fact  that  some  vendors
600       make  their applications spit out lines styled this way.
601
602       If there is really bad "CSV" data, like
603
604        1,"foo "bar" baz",42
605
606       or
607
608        1,""foo bar baz"",42
609
610       there is a way to get this data-line parsed and leave the quotes inside
611       the quoted field as-is.  This can be achieved by setting
612       "allow_loose_quotes" AND making sure that the "escape_char" is  not
613       equal to "quote_char".
614
615       allow_loose_escapes
616
617        my $csv = Text::CSV_XS->new ({ allow_loose_escapes => 1 });
618                $csv->allow_loose_escapes (0);
619        my $f = $csv->allow_loose_escapes;
620
621       Parsing fields  that  have  "escape_char"  characters that escape
622       characters that do not need to be escaped, like:
623
624        my $csv = Text::CSV_XS->new ({ escape_char => "\\" });
625        $csv->parse (qq{1,"my bar\'s",baz,42});
626
627       would result in parse error 2025.   Though it is bad practice to allow
628       this format,  this attribute enables you to treat all escape character
629       sequences equal.
630
631       allow_unquoted_escape
632
633        my $csv = Text::CSV_XS->new ({ allow_unquoted_escape => 1 });
634                $csv->allow_unquoted_escape (0);
635        my $f = $csv->allow_unquoted_escape;
636
637       A backward compatibility issue where "escape_char" differs from
638       "quote_char"  prevents  "escape_char" to be in the first position of a
639       field.  If "quote_char" is equal to the default """ and "escape_char"
640       is set to "\", this would be illegal:
641
642        1,\0,2
643
644       Setting this attribute to 1  might help to overcome issues with
645       backward compatibility and allow this style.
646
647       always_quote
648
649        my $csv = Text::CSV_XS->new ({ always_quote => 1 });
650                $csv->always_quote (0);
651        my $f = $csv->always_quote;
652
653       By default the generated fields are quoted only if they need to be.
654       For example, if they contain the separator character. If you set this
655       attribute to 1 then all defined fields will be quoted. ("undef" fields
656       are not quoted, see "blank_is_undef"). This makes it quite often easier
657       to handle exported data in external applications.   (Poor creatures who
658       are better to use Text::CSV_XS. :)
659
660       quote_space
661
662        my $csv = Text::CSV_XS->new ({ quote_space => 1 });
663                $csv->quote_space (0);
664        my $f = $csv->quote_space;
665
666       By default,  a space in a field would trigger quotation.  As no rule
667       exists this to be forced in "CSV",  nor any for the opposite, the
668       default is true for safety.   You can exclude the space  from this
669       trigger  by setting this attribute to 0.
670
671       quote_empty
672
673        my $csv = Text::CSV_XS->new ({ quote_empty => 1 });
674                $csv->quote_empty (0);
675        my $f = $csv->quote_empty;
676
677       By default the generated fields are quoted only if they need to be.
678       An empty (defined) field does not need quotation. If you set this
679       attribute to 1 then empty defined fields will be quoted.  ("undef"
680       fields are not quoted, see "blank_is_undef"). See also "always_quote".
681
682       quote_binary
683
684        my $csv = Text::CSV_XS->new ({ quote_binary => 1 });
685                $csv->quote_binary (0);
686        my $f = $csv->quote_binary;
687
688       By default,  all "unsafe" bytes inside a string cause the combined
689       field to be quoted.  By setting this attribute to 0, you can disable
690       that trigger for bytes >= 0x7F.
691
692       escape_null
693
694        my $csv = Text::CSV_XS->new ({ escape_null => 1 });
695                $csv->escape_null (0);
696        my $f = $csv->escape_null;
697
698       By default, a "NULL" byte in a field would be escaped. This option
699       enables you to treat the  "NULL"  byte as a simple binary character in
700       binary mode (the "{ binary => 1 }" is set).  The default is true.  You
701       can prevent "NULL" escapes by setting this attribute to 0.
702
703       When the "escape_char" attribute is set to undefined,  this attribute
704       will be set to false.
705
706       The default setting will encode "=\x00=" as
707
708        "="0="
709
710       With "escape_null" set, this will result in
711
712        "=\x00="
713
714       The default when using the "csv" function is "false".
715
716       For backward compatibility reasons,  the deprecated old name
717       "quote_null" is still recognized.
718
719       keep_meta_info
720
721        my $csv = Text::CSV_XS->new ({ keep_meta_info => 1 });
722                $csv->keep_meta_info (0);
723        my $f = $csv->keep_meta_info;
724
725       By default, the parsing of input records is as simple and fast as
726       possible.  However,  some parsing information - like quotation of the
727       original field - is lost in that process.  Setting this flag to true
728       enables retrieving that information after parsing with  the methods
729       "meta_info",  "is_quoted", and "is_binary" described below.  Default is
730       false for performance.
731
732       If you set this attribute to a value greater than 9,   then you can
733       control output quotation style like it was used in the input of the the
734       last parsed record (unless quotation was added because of other
735       reasons).
736
737        my $csv = Text::CSV_XS->new ({
738           binary         => 1,
739           keep_meta_info => 1,
740           quote_space    => 0,
741           });
742
743        my $row = $csv->parse (q{1,,"", ," ",f,"g","h""h",help,"help"});
744
745        $csv->print (*STDOUT, \@row);
746        # 1,,, , ,f,g,"h""h",help,help
747        $csv->keep_meta_info (11);
748        $csv->print (*STDOUT, \@row);
749        # 1,,"", ," ",f,"g","h""h",help,"help"
750
751       undef_str
752
753        my $csv = Text::CSV_XS->new ({ undef_str => "\\N" });
754                $csv->undef_str (undef);
755        my $s = $csv->undef_str;
756
757       This attribute optionally defines the output of undefined fields. The
758       value passed is not changed at all, so if it needs quotation, the
759       quotation needs to be included in the value of the attribute.  Use with
760       caution, as passing a value like  ",",,,,"""  will for sure mess up
761       your output. The default for this attribute is "undef", meaning no
762       special treatment.
763
764       This attribute is useful when exporting  CSV data  to be imported in
765       custom loaders, like for MySQL, that recognize special sequences for
766       "NULL" data.
767
768       This attribute has no meaning when parsing CSV data.
769
770       comment_str
771
772        my $csv = Text::CSV_XS->new ({ comment_str => "#" });
773                $csv->comment_str (undef);
774        my $s = $csv->comment_str;
775
776       This attribute optionally defines a string to be recognized as comment.
777       If this attribute is defined,   all lines starting with this sequence
778       will not be parsed as CSV but skipped as comment.
779
780       This attribute has no meaning when generating CSV.
781
782       Comment strings that start with any of the special characters/sequences
783       are not supported (so it cannot start with any of "sep_char",
784       "quote_char", "escape_char", "sep", "quote", or "eol").
785
786       For convenience, "comment" is an alias for "comment_str".
787
788       verbatim
789
790        my $csv = Text::CSV_XS->new ({ verbatim => 1 });
791                $csv->verbatim (0);
792        my $f = $csv->verbatim;
793
794       This is a quite controversial attribute to set,  but makes some hard
795       things possible.
796
797       The rationale behind this attribute is to tell the parser that the
798       normally special characters newline ("NL") and Carriage Return ("CR")
799       will not be special when this flag is set,  and be dealt with  as being
800       ordinary binary characters. This will ease working with data with
801       embedded newlines.
802
803       When  "verbatim"  is used with  "getline",  "getline"  auto-"chomp"'s
804       every line.
805
806       Imagine a file format like
807
808        M^^Hans^Janssen^Klas 2\n2A^Ja^11-06-2007#\r\n
809
810       where, the line ending is a very specific "#\r\n", and the sep_char is
811       a "^" (caret).   None of the fields is quoted,   but embedded binary
812       data is likely to be present. With the specific line ending, this
813       should not be too hard to detect.
814
815       By default,  Text::CSV_XS'  parse function is instructed to only know
816       about "\n" and "\r"  to be legal line endings,  and so has to deal with
817       the embedded newline as a real "end-of-line",  so it can scan the next
818       line if binary is true, and the newline is inside a quoted field. With
819       this option, we tell "parse" to parse the line as if "\n" is just
820       nothing more than a binary character.
821
822       For "parse" this means that the parser has no more idea about line
823       ending and "getline" "chomp"s line endings on reading.
824
825       types
826
827       A set of column types; the attribute is immediately passed to the
828       "types" method.
829
830       callbacks
831
832       See the "Callbacks" section below.
833
834       accessors
835
836       To sum it up,
837
838        $csv = Text::CSV_XS->new ();
839
840       is equivalent to
841
842        $csv = Text::CSV_XS->new ({
843            eol                   => undef, # \r, \n, or \r\n
844            sep_char              => ',',
845            sep                   => undef,
846            quote_char            => '"',
847            quote                 => undef,
848            escape_char           => '"',
849            binary                => 0,
850            decode_utf8           => 1,
851            auto_diag             => 0,
852            diag_verbose          => 0,
853            blank_is_undef        => 0,
854            empty_is_undef        => 0,
855            allow_whitespace      => 0,
856            allow_loose_quotes    => 0,
857            allow_loose_escapes   => 0,
858            allow_unquoted_escape => 0,
859            always_quote          => 0,
860            quote_empty           => 0,
861            quote_space           => 1,
862            escape_null           => 1,
863            quote_binary          => 1,
864            keep_meta_info        => 0,
865            strict                => 0,
866            skip_empty_rows       => 0,
867            formula               => 0,
868            verbatim              => 0,
869            undef_str             => undef,
870            comment_str           => undef,
871            types                 => undef,
872            callbacks             => undef,
873            });
874
875       For all of the above mentioned flags, an accessor method is available
876       where you can inquire the current value, or change the value
877
878        my $quote = $csv->quote_char;
879        $csv->binary (1);
880
881       It is not wise to change these settings halfway through writing "CSV"
882       data to a stream. If however you want to create a new stream using the
883       available "CSV" object, there is no harm in changing them.
884
885       If the "new" constructor call fails,  it returns "undef",  and makes
886       the fail reason available through the "error_diag" method.
887
888        $csv = Text::CSV_XS->new ({ ecs_char => 1 }) or
889            die "".Text::CSV_XS->error_diag ();
890
891       "error_diag" will return a string like
892
893        "INI - Unknown attribute 'ecs_char'"
894
895   known_attributes
896        @attr = Text::CSV_XS->known_attributes;
897        @attr = Text::CSV_XS::known_attributes;
898        @attr = $csv->known_attributes;
899
900       This method will return an ordered list of all the supported
901       attributes as described above.   This can be useful for knowing what
902       attributes are valid in classes that use or extend Text::CSV_XS.
903
904   print
905        $status = $csv->print ($fh, $colref);
906
907       Similar to  "combine" + "string" + "print",  but much more efficient.
908       It expects an array ref as input  (not an array!)  and the resulting
909       string is not really  created,  but  immediately  written  to the  $fh
910       object, typically an IO handle or any other object that offers a
911       "print" method.
912
913       For performance reasons  "print"  does not create a result string,  so
914       all "string", "status", "fields", and "error_input" methods will return
915       undefined information after executing this method.
916
917       If $colref is "undef"  (explicit,  not through a variable argument) and
918       "bind_columns"  was used to specify fields to be printed,  it is
919       possible to make performance improvements, as otherwise data would have
920       to be copied as arguments to the method call:
921
922        $csv->bind_columns (\($foo, $bar));
923        $status = $csv->print ($fh, undef);
924
925       A short benchmark
926
927        my @data = ("aa" .. "zz");
928        $csv->bind_columns (\(@data));
929
930        $csv->print ($fh, [ @data ]);   # 11800 recs/sec
931        $csv->print ($fh,  \@data  );   # 57600 recs/sec
932        $csv->print ($fh,   undef  );   # 48500 recs/sec
933
934   say
935        $status = $csv->say ($fh, $colref);
936
937       Like "print", but "eol" defaults to "$\".
938
939   print_hr
940        $csv->print_hr ($fh, $ref);
941
942       Provides an easy way  to print a  $ref  (as fetched with "getline_hr")
943       provided the column names are set with "column_names".
944
945       It is just a wrapper method with basic parameter checks over
946
947        $csv->print ($fh, [ map { $ref->{$_} } $csv->column_names ]);
948
949   combine
950        $status = $csv->combine (@fields);
951
952       This method constructs a "CSV" record from  @fields,  returning success
953       or failure.   Failure can result from lack of arguments or an argument
954       that contains an invalid character.   Upon success,  "string" can be
955       called to retrieve the resultant "CSV" string.  Upon failure,  the
956       value returned by "string" is undefined and "error_input" could be
957       called to retrieve the invalid argument.
958
959   string
960        $line = $csv->string ();
961
962       This method returns the input to  "parse"  or the resultant "CSV"
963       string of "combine", whichever was called more recently.
964
965   getline
966        $colref = $csv->getline ($fh);
967
968       This is the counterpart to  "print",  as "parse"  is the counterpart to
969       "combine":  it parses a row from the $fh  handle using the "getline"
970       method associated with $fh  and parses this row into an array ref.
971       This array ref is returned by the function or "undef" for failure.
972       When $fh does not support "getline", you are likely to hit errors.
973
974       When fields are bound with "bind_columns" the return value is a
975       reference to an empty list.
976
977       The "string", "fields", and "status" methods are meaningless again.
978
979   getline_all
980        $arrayref = $csv->getline_all ($fh);
981        $arrayref = $csv->getline_all ($fh, $offset);
982        $arrayref = $csv->getline_all ($fh, $offset, $length);
983
984       This will return a reference to a list of getline ($fh) results.  In
985       this call, "keep_meta_info" is disabled.  If $offset is negative, as
986       with "splice", only the last  "abs ($offset)" records of $fh are taken
987       into consideration.
988
989       Given a CSV file with 10 lines:
990
991        lines call
992        ----- ---------------------------------------------------------
993        0..9  $csv->getline_all ($fh)         # all
994        0..9  $csv->getline_all ($fh,  0)     # all
995        8..9  $csv->getline_all ($fh,  8)     # start at 8
996        -     $csv->getline_all ($fh,  0,  0) # start at 0 first 0 rows
997        0..4  $csv->getline_all ($fh,  0,  5) # start at 0 first 5 rows
998        4..5  $csv->getline_all ($fh,  4,  2) # start at 4 first 2 rows
999        8..9  $csv->getline_all ($fh, -2)     # last 2 rows
1000        6..7  $csv->getline_all ($fh, -4,  2) # first 2 of last  4 rows
1001
1002   getline_hr
1003       The "getline_hr" and "column_names" methods work together  to allow you
1004       to have rows returned as hashrefs.  You must call "column_names" first
1005       to declare your column names.
1006
1007        $csv->column_names (qw( code name price description ));
1008        $hr = $csv->getline_hr ($fh);
1009        print "Price for $hr->{name} is $hr->{price} EUR\n";
1010
1011       "getline_hr" will croak if called before "column_names".
1012
1013       Note that  "getline_hr"  creates a hashref for every row and will be
1014       much slower than the combined use of "bind_columns"  and "getline" but
1015       still offering the same easy to use hashref inside the loop:
1016
1017        my @cols = @{$csv->getline ($fh)};
1018        $csv->column_names (@cols);
1019        while (my $row = $csv->getline_hr ($fh)) {
1020            print $row->{price};
1021            }
1022
1023       Could easily be rewritten to the much faster:
1024
1025        my @cols = @{$csv->getline ($fh)};
1026        my $row = {};
1027        $csv->bind_columns (\@{$row}{@cols});
1028        while ($csv->getline ($fh)) {
1029            print $row->{price};
1030            }
1031
1032       Your mileage may vary for the size of the data and the number of rows.
1033       With perl-5.14.2 the comparison for a 100_000 line file with 14
1034       columns:
1035
1036                   Rate hashrefs getlines
1037        hashrefs 1.00/s       --     -76%
1038        getlines 4.15/s     313%       --
1039
1040   getline_hr_all
1041        $arrayref = $csv->getline_hr_all ($fh);
1042        $arrayref = $csv->getline_hr_all ($fh, $offset);
1043        $arrayref = $csv->getline_hr_all ($fh, $offset, $length);
1044
1045       This will return a reference to a list of   getline_hr ($fh) results.
1046       In this call, "keep_meta_info" is disabled.
1047
1048   parse
1049        $status = $csv->parse ($line);
1050
1051       This method decomposes a  "CSV"  string into fields,  returning success
1052       or failure.   Failure can result from a lack of argument  or the given
1053       "CSV" string is improperly formatted.   Upon success, "fields" can be
1054       called to retrieve the decomposed fields. Upon failure calling "fields"
1055       will return undefined data and  "error_input"  can be called to
1056       retrieve  the invalid argument.
1057
1058       You may use the "types"  method for setting column types.  See "types"'
1059       description below.
1060
1061       The $line argument is supposed to be a simple scalar. Everything else
1062       is supposed to croak and set error 1500.
1063
1064   fragment
1065       This function tries to implement RFC7111  (URI Fragment Identifiers for
1066       the text/csv Media Type) - http://tools.ietf.org/html/rfc7111
1067
1068        my $AoA = $csv->fragment ($fh, $spec);
1069
1070       In specifications,  "*" is used to specify the last item, a dash ("-")
1071       to indicate a range.   All indices are 1-based:  the first row or
1072       column has index 1. Selections can be combined with the semi-colon
1073       (";").
1074
1075       When using this method in combination with  "column_names",  the
1076       returned reference  will point to a  list of hashes  instead of a  list
1077       of lists.  A disjointed  cell-based combined selection  might return
1078       rows with different number of columns making the use of hashes
1079       unpredictable.
1080
1081        $csv->column_names ("Name", "Age");
1082        my $AoH = $csv->fragment ($fh, "col=3;8");
1083
1084       If the "after_parse" callback is active,  it is also called on every
1085       line parsed and skipped before the fragment.
1086
1087       row
1088          row=4
1089          row=5-7
1090          row=6-*
1091          row=1-2;4;6-*
1092
1093       col
1094          col=2
1095          col=1-3
1096          col=4-*
1097          col=1-2;4;7-*
1098
1099       cell
1100         In cell-based selection, the comma (",") is used to pair row and
1101         column
1102
1103          cell=4,1
1104
1105         The range operator ("-") using "cell"s can be used to define top-left
1106         and bottom-right "cell" location
1107
1108          cell=3,1-4,6
1109
1110         The "*" is only allowed in the second part of a pair
1111
1112          cell=3,2-*,2    # row 3 till end, only column 2
1113          cell=3,2-3,*    # column 2 till end, only row 3
1114          cell=3,2-*,*    # strip row 1 and 2, and column 1
1115
1116         Cells and cell ranges may be combined with ";", possibly resulting in
1117         rows with different numbers of columns
1118
1119          cell=1,1-2,2;3,3-4,4;1,4;4,1
1120
1121         Disjointed selections will only return selected cells.   The cells
1122         that are not  specified  will  not  be  included  in the  returned
1123         set,  not even as "undef".  As an example given a "CSV" like
1124
1125          11,12,13,...19
1126          21,22,...28,29
1127          :            :
1128          91,...97,98,99
1129
1130         with "cell=1,1-2,2;3,3-4,4;1,4;4,1" will return:
1131
1132          11,12,14
1133          21,22
1134          33,34
1135          41,43,44
1136
1137         Overlapping cell-specs will return those cells only once, So
1138         "cell=1,1-3,3;2,2-4,4;2,3;4,2" will return:
1139
1140          11,12,13
1141          21,22,23,24
1142          31,32,33,34
1143          42,43,44
1144
1145       RFC7111 <http://tools.ietf.org/html/rfc7111> does  not  allow different
1146       types of specs to be combined   (either "row" or "col" or "cell").
1147       Passing an invalid fragment specification will croak and set error
1148       2013.
1149
1150   column_names
1151       Set the "keys" that will be used in the  "getline_hr"  calls.  If no
1152       keys (column names) are passed, it will return the current setting as a
1153       list.
1154
1155       "column_names" accepts a list of scalars  (the column names)  or a
1156       single array_ref, so you can pass the return value from "getline" too:
1157
1158        $csv->column_names ($csv->getline ($fh));
1159
1160       "column_names" does no checking on duplicates at all, which might lead
1161       to unexpected results.   Undefined entries will be replaced with the
1162       string "\cAUNDEF\cA", so
1163
1164        $csv->column_names (undef, "", "name", "name");
1165        $hr = $csv->getline_hr ($fh);
1166
1167       will set "$hr->{"\cAUNDEF\cA"}" to the 1st field,  "$hr->{""}" to the
1168       2nd field, and "$hr->{name}" to the 4th field,  discarding the 3rd
1169       field.
1170
1171       "column_names" croaks on invalid arguments.
1172
1173   header
1174       This method does NOT work in perl-5.6.x
1175
1176       Parse the CSV header and set "sep", column_names and encoding.
1177
1178        my @hdr = $csv->header ($fh);
1179        $csv->header ($fh, { sep_set => [ ";", ",", "|", "\t" ] });
1180        $csv->header ($fh, { detect_bom => 1, munge_column_names => "lc" });
1181
1182       The first argument should be a file handle.
1183
1184       This method resets some object properties,  as it is supposed to be
1185       invoked only once per file or stream.  It will leave attributes
1186       "column_names" and "bound_columns" alone if setting column names is
1187       disabled. Reading headers on previously process objects might fail on
1188       perl-5.8.0 and older.
1189
1190       Assuming that the file opened for parsing has a header, and the header
1191       does not contain problematic characters like embedded newlines,   read
1192       the first line from the open handle then auto-detect whether the header
1193       separates the column names with a character from the allowed separator
1194       list.
1195
1196       If any of the allowed separators matches,  and none of the other
1197       allowed separators match,  set  "sep"  to that  separator  for the
1198       current CSV_XS instance and use it to parse the first line, map those
1199       to lowercase, and use that to set the instance "column_names":
1200
1201        my $csv = Text::CSV_XS->new ({ binary => 1, auto_diag => 1 });
1202        open my $fh, "<", "file.csv";
1203        binmode $fh; # for Windows
1204        $csv->header ($fh);
1205        while (my $row = $csv->getline_hr ($fh)) {
1206            ...
1207            }
1208
1209       If the header is empty,  contains more than one unique separator out of
1210       the allowed set,  contains empty fields,   or contains identical fields
1211       (after folding), it will croak with error 1010, 1011, 1012, or 1013
1212       respectively.
1213
1214       If the header contains embedded newlines or is not valid  CSV  in any
1215       other way, this method will croak and leave the parse error untouched.
1216
1217       A successful call to "header"  will always set the  "sep"  of the $csv
1218       object. This behavior can not be disabled.
1219
1220       return value
1221
1222       On error this method will croak.
1223
1224       In list context,  the headers will be returned whether they are used to
1225       set "column_names" or not.
1226
1227       In scalar context, the instance itself is returned.  Note: the values
1228       as found in the header will effectively be  lost if  "set_column_names"
1229       is false.
1230
1231       Options
1232
1233       sep_set
1234          $csv->header ($fh, { sep_set => [ ";", ",", "|", "\t" ] });
1235
1236         The list of legal separators defaults to "[ ";", "," ]" and can be
1237         changed by this option.  As this is probably the most often used
1238         option,  it can be passed on its own as an unnamed argument:
1239
1240          $csv->header ($fh, [ ";", ",", "|", "\t", "::", "\x{2063}" ]);
1241
1242         Multi-byte  sequences are allowed,  both multi-character and
1243         Unicode.  See "sep".
1244
1245       detect_bom
1246          $csv->header ($fh, { detect_bom => 1 });
1247
1248         The default behavior is to detect if the header line starts with a
1249         BOM.  If the header has a BOM, use that to set the encoding of $fh.
1250         This default behavior can be disabled by passing a false value to
1251         "detect_bom".
1252
1253         Supported encodings from BOM are: UTF-8, UTF-16BE, UTF-16LE,
1254         UTF-32BE,  and UTF-32LE. BOM also supports UTF-1, UTF-EBCDIC, SCSU,
1255         BOCU-1,  and GB-18030 but Encode does not (yet). UTF-7 is not
1256         supported.
1257
1258         If a supported BOM was detected as start of the stream, it is stored
1259         in the object attribute "ENCODING".
1260
1261          my $enc = $csv->{ENCODING};
1262
1263         The encoding is used with "binmode" on $fh.
1264
1265         If the handle was opened in a (correct) encoding,  this method will
1266         not alter the encoding, as it checks the leading bytes of the first
1267         line. In case the stream starts with a decoded BOM ("U+FEFF"),
1268         "{ENCODING}" will be "" (empty) instead of the default "undef".
1269
1270       munge_column_names
1271         This option offers the means to modify the column names into
1272         something that is most useful to the application.   The default is to
1273         map all column names to lower case.
1274
1275          $csv->header ($fh, { munge_column_names => "lc" });
1276
1277         The following values are available:
1278
1279           lc     - lower case
1280           uc     - upper case
1281           db     - valid DB field names
1282           none   - do not change
1283           \%hash - supply a mapping
1284           \&cb   - supply a callback
1285
1286         Lower case
1287            $csv->header ($fh, { munge_column_names => "lc" });
1288
1289           The header is changed to all lower-case
1290
1291            $_ = lc;
1292
1293         Upper case
1294            $csv->header ($fh, { munge_column_names => "uc" });
1295
1296           The header is changed to all upper-case
1297
1298            $_ = uc;
1299
1300         Literal
1301            $csv->header ($fh, { munge_column_names => "none" });
1302
1303         Hash
1304            $csv->header ($fh, { munge_column_names => { foo => "sombrero" });
1305
1306           if a value does not exist, the original value is used unchanged
1307
1308         Database
1309            $csv->header ($fh, { munge_column_names => "db" });
1310
1311           - lower-case
1312
1313           - all sequences of non-word characters are replaced with an
1314             underscore
1315
1316           - all leading underscores are removed
1317
1318            $_ = lc (s/\W+/_/gr =~ s/^_+//r);
1319
1320         Callback
1321            $csv->header ($fh, { munge_column_names => sub { fc } });
1322            $csv->header ($fh, { munge_column_names => sub { "column_".$col++ } });
1323            $csv->header ($fh, { munge_column_names => sub { lc (s/\W+/_/gr) } });
1324
1325           As this callback is called in a "map", you can use $_ directly.
1326
1327       set_column_names
1328          $csv->header ($fh, { set_column_names => 1 });
1329
1330         The default is to set the instances column names using
1331         "column_names" if the method is successful,  so subsequent calls to
1332         "getline_hr" can return a hash. Disable setting the header can be
1333         forced by using a false value for this option.
1334
1335         As described in "return value" above, content is lost in scalar
1336         context.
1337
1338       Validation
1339
1340       When receiving CSV files from external sources,  this method can be
1341       used to protect against changes in the layout by restricting to known
1342       headers  (and typos in the header fields).
1343
1344        my %known = (
1345            "record key" => "c_rec",
1346            "rec id"     => "c_rec",
1347            "id_rec"     => "c_rec",
1348            "kode"       => "code",
1349            "code"       => "code",
1350            "vaule"      => "value",
1351            "value"      => "value",
1352            );
1353        my $csv = Text::CSV_XS->new ({ binary => 1, auto_diag => 1 });
1354        open my $fh, "<", $source or die "$source: $!";
1355        $csv->header ($fh, { munge_column_names => sub {
1356            s/\s+$//;
1357            s/^\s+//;
1358            $known{lc $_} or die "Unknown column '$_' in $source";
1359            }});
1360        while (my $row = $csv->getline_hr ($fh)) {
1361            say join "\t", $row->{c_rec}, $row->{code}, $row->{value};
1362            }
1363
1364   bind_columns
1365       Takes a list of scalar references to be used for output with  "print"
1366       or to store in the fields fetched by "getline".  When you do not pass
1367       enough references to store the fetched fields in, "getline" will fail
1368       with error 3006.  If you pass more than there are fields to return,
1369       the content of the remaining references is left untouched.
1370
1371        $csv->bind_columns (\$code, \$name, \$price, \$description);
1372        while ($csv->getline ($fh)) {
1373            print "The price of a $name is \x{20ac} $price\n";
1374            }
1375
1376       To reset or clear all column binding, call "bind_columns" with the
1377       single argument "undef". This will also clear column names.
1378
1379        $csv->bind_columns (undef);
1380
1381       If no arguments are passed at all, "bind_columns" will return the list
1382       of current bindings or "undef" if no binds are active.
1383
1384       Note that in parsing with  "bind_columns",  the fields are set on the
1385       fly.  That implies that if the third field of a row causes an error
1386       (or this row has just two fields where the previous row had more),  the
1387       first two fields already have been assigned the values of the current
1388       row, while the rest of the fields will still hold the values of the
1389       previous row.  If you want the parser to fail in these cases, use the
1390       "strict" attribute.
1391
1392   eof
1393        $eof = $csv->eof ();
1394
1395       If "parse" or  "getline"  was used with an IO stream,  this method will
1396       return true (1) if the last call hit end of file,  otherwise it will
1397       return false ('').  This is useful to see the difference between a
1398       failure and end of file.
1399
1400       Note that if the parsing of the last line caused an error,  "eof" is
1401       still true.  That means that if you are not using "auto_diag", an idiom
1402       like
1403
1404        while (my $row = $csv->getline ($fh)) {
1405            # ...
1406            }
1407        $csv->eof or $csv->error_diag;
1408
1409       will not report the error. You would have to change that to
1410
1411        while (my $row = $csv->getline ($fh)) {
1412            # ...
1413            }
1414        +$csv->error_diag and $csv->error_diag;
1415
1416   types
1417        $csv->types (\@tref);
1418
1419       This method is used to force that  (all)  columns are of a given type.
1420       For example, if you have an integer column,  two  columns  with
1421       doubles  and a string column, then you might do a
1422
1423        $csv->types ([Text::CSV_XS::IV (),
1424                      Text::CSV_XS::NV (),
1425                      Text::CSV_XS::NV (),
1426                      Text::CSV_XS::PV ()]);
1427
1428       Column types are used only for decoding columns while parsing,  in
1429       other words by the "parse" and "getline" methods.
1430
1431       You can unset column types by doing a
1432
1433        $csv->types (undef);
1434
1435       or fetch the current type settings with
1436
1437        $types = $csv->types ();
1438
1439       IV  Set field type to integer.
1440
1441       NV  Set field type to numeric/float.
1442
1443       PV  Set field type to string.
1444
1445   fields
1446        @columns = $csv->fields ();
1447
1448       This method returns the input to   "combine"  or the resultant
1449       decomposed fields of a successful "parse", whichever was called more
1450       recently.
1451
1452       Note that the return value is undefined after using "getline", which
1453       does not fill the data structures returned by "parse".
1454
1455   meta_info
1456        @flags = $csv->meta_info ();
1457
1458       This method returns the "flags" of the input to "combine" or the flags
1459       of the resultant  decomposed fields of  "parse",   whichever was called
1460       more recently.
1461
1462       For each field,  a meta_info field will hold  flags that  inform
1463       something about  the  field  returned  by  the  "fields"  method or
1464       passed to  the "combine" method. The flags are bit-wise-"or"'d like:
1465
1466       " "0x0001
1467         The field was quoted.
1468
1469       " "0x0002
1470         The field was binary.
1471
1472       See the "is_***" methods below.
1473
1474   is_quoted
1475        my $quoted = $csv->is_quoted ($column_idx);
1476
1477       where  $column_idx is the  (zero-based)  index of the column in the
1478       last result of "parse".
1479
1480       This returns a true value  if the data in the indicated column was
1481       enclosed in "quote_char" quotes.  This might be important for fields
1482       where content ",20070108," is to be treated as a numeric value,  and
1483       where ","20070108"," is explicitly marked as character string data.
1484
1485       This method is only valid when "keep_meta_info" is set to a true value.
1486
1487   is_binary
1488        my $binary = $csv->is_binary ($column_idx);
1489
1490       where  $column_idx is the  (zero-based)  index of the column in the
1491       last result of "parse".
1492
1493       This returns a true value if the data in the indicated column contained
1494       any byte in the range "[\x00-\x08,\x10-\x1F,\x7F-\xFF]".
1495
1496       This method is only valid when "keep_meta_info" is set to a true value.
1497
1498   is_missing
1499        my $missing = $csv->is_missing ($column_idx);
1500
1501       where  $column_idx is the  (zero-based)  index of the column in the
1502       last result of "getline_hr".
1503
1504        $csv->keep_meta_info (1);
1505        while (my $hr = $csv->getline_hr ($fh)) {
1506            $csv->is_missing (0) and next; # This was an empty line
1507            }
1508
1509       When using  "getline_hr",  it is impossible to tell if the  parsed
1510       fields are "undef" because they where not filled in the "CSV" stream
1511       or because they were not read at all, as all the fields defined by
1512       "column_names" are set in the hash-ref.    If you still need to know if
1513       all fields in each row are provided, you should enable "keep_meta_info"
1514       so you can check the flags.
1515
1516       If  "keep_meta_info"  is "false",  "is_missing"  will always return
1517       "undef", regardless of $column_idx being valid or not. If this
1518       attribute is "true" it will return either 0 (the field is present) or 1
1519       (the field is missing).
1520
1521       A special case is the empty line.  If the line is completely empty -
1522       after dealing with the flags - this is still a valid CSV line:  it is a
1523       record of just one single empty field. However, if "keep_meta_info" is
1524       set, invoking "is_missing" with index 0 will now return true.
1525
1526   status
1527        $status = $csv->status ();
1528
1529       This method returns the status of the last invoked "combine" or "parse"
1530       call. Status is success (true: 1) or failure (false: "undef" or 0).
1531
1532       Note that as this only keeps track of the status of above mentioned
1533       methods, you are probably looking for "error_diag" instead.
1534
1535   error_input
1536        $bad_argument = $csv->error_input ();
1537
1538       This method returns the erroneous argument (if it exists) of "combine"
1539       or "parse",  whichever was called more recently.  If the last
1540       invocation was successful, "error_input" will return "undef".
1541
1542       Depending on the type of error, it might also hold the data for the
1543       last error-input of "getline".
1544
1545   error_diag
1546        Text::CSV_XS->error_diag ();
1547        $csv->error_diag ();
1548        $error_code               = 0  + $csv->error_diag ();
1549        $error_str                = "" . $csv->error_diag ();
1550        ($cde, $str, $pos, $rec, $fld) = $csv->error_diag ();
1551
1552       If (and only if) an error occurred,  this function returns  the
1553       diagnostics of that error.
1554
1555       If called in void context,  this will print the internal error code and
1556       the associated error message to STDERR.
1557
1558       If called in list context,  this will return  the error code  and the
1559       error message in that order.  If the last error was from parsing, the
1560       rest of the values returned are a best guess at the location  within
1561       the line  that was being parsed. Their values are 1-based.  The
1562       position currently is index of the byte at which the parsing failed in
1563       the current record. It might change to be the index of the current
1564       character in a later release. The records is the index of the record
1565       parsed by the csv instance. The field number is the index of the field
1566       the parser thinks it is currently  trying to  parse. See
1567       examples/csv-check for how this can be used.
1568
1569       If called in  scalar context,  it will return  the diagnostics  in a
1570       single scalar, a-la $!.  It will contain the error code in numeric
1571       context, and the diagnostics message in string context.
1572
1573       When called as a class method or a  direct function call,  the
1574       diagnostics are that of the last "new" call.
1575
1576   record_number
1577        $recno = $csv->record_number ();
1578
1579       Returns the records parsed by this csv instance.  This value should be
1580       more accurate than $. when embedded newlines come in play. Records
1581       written by this instance are not counted.
1582
1583   SetDiag
1584        $csv->SetDiag (0);
1585
1586       Use to reset the diagnostics if you are dealing with errors.
1587

FUNCTIONS

1589   csv
1590       This function is not exported by default and should be explicitly
1591       requested:
1592
1593        use Text::CSV_XS qw( csv );
1594
1595       This is a high-level function that aims at simple (user) interfaces.
1596       This can be used to read/parse a "CSV" file or stream (the default
1597       behavior) or to produce a file or write to a stream (define the  "out"
1598       attribute).  It returns an array- or hash-reference on parsing (or
1599       "undef" on fail) or the numeric value of  "error_diag"  on writing.
1600       When this function fails you can get to the error using the class call
1601       to "error_diag"
1602
1603        my $aoa = csv (in => "test.csv") or
1604            die Text::CSV_XS->error_diag;
1605
1606       This function takes the arguments as key-value pairs. This can be
1607       passed as a list or as an anonymous hash:
1608
1609        my $aoa = csv (  in => "test.csv", sep_char => ";");
1610        my $aoh = csv ({ in => $fh, headers => "auto" });
1611
1612       The arguments passed consist of two parts:  the arguments to "csv"
1613       itself and the optional attributes to the  "CSV"  object used inside
1614       the function as enumerated and explained in "new".
1615
1616       If not overridden, the default option used for CSV is
1617
1618        auto_diag   => 1
1619        escape_null => 0
1620
1621       The option that is always set and cannot be altered is
1622
1623        binary      => 1
1624
1625       As this function will likely be used in one-liners,  it allows  "quote"
1626       to be abbreviated as "quo",  and  "escape_char" to be abbreviated as
1627       "esc" or "escape".
1628
1629       Alternative invocations:
1630
1631        my $aoa = Text::CSV_XS::csv (in => "file.csv");
1632
1633        my $csv = Text::CSV_XS->new ();
1634        my $aoa = $csv->csv (in => "file.csv");
1635
1636       In the latter case, the object attributes are used from the existing
1637       object and the attribute arguments in the function call are ignored:
1638
1639        my $csv = Text::CSV_XS->new ({ sep_char => ";" });
1640        my $aoh = $csv->csv (in => "file.csv", bom => 1);
1641
1642       will parse using ";" as "sep_char", not ",".
1643
1644       in
1645
1646       Used to specify the source.  "in" can be a file name (e.g. "file.csv"),
1647       which will be  opened for reading  and closed when finished,  a file
1648       handle (e.g.  $fh or "FH"),  a reference to a glob (e.g. "\*ARGV"),
1649       the glob itself (e.g. *STDIN), or a reference to a scalar (e.g.
1650       "\q{1,2,"csv"}").
1651
1652       When used with "out", "in" should be a reference to a CSV structure
1653       (AoA or AoH)  or a CODE-ref that returns an array-reference or a hash-
1654       reference.  The code-ref will be invoked with no arguments.
1655
1656        my $aoa = csv (in => "file.csv");
1657
1658        open my $fh, "<", "file.csv";
1659        my $aoa = csv (in => $fh);
1660
1661        my $csv = [ [qw( Foo Bar )], [ 1, 2 ], [ 2, 3 ]];
1662        my $err = csv (in => $csv, out => "file.csv");
1663
1664       If called in void context without the "out" attribute, the resulting
1665       ref will be used as input to a subsequent call to csv:
1666
1667        csv (in => "file.csv", filter => { 2 => sub { length > 2 }})
1668
1669       will be a shortcut to
1670
1671        csv (in => csv (in => "file.csv", filter => { 2 => sub { length > 2 }}))
1672
1673       where, in the absence of the "out" attribute, this is a shortcut to
1674
1675        csv (in  => csv (in => "file.csv", filter => { 2 => sub { length > 2 }}),
1676             out => *STDOUT)
1677
1678       out
1679
1680        csv (in => $aoa, out => "file.csv");
1681        csv (in => $aoa, out => $fh);
1682        csv (in => $aoa, out =>   STDOUT);
1683        csv (in => $aoa, out =>  *STDOUT);
1684        csv (in => $aoa, out => \*STDOUT);
1685        csv (in => $aoa, out => \my $data);
1686        csv (in => $aoa, out =>  undef);
1687        csv (in => $aoa, out => \"skip");
1688
1689        csv (in => $fh,  out => \@aoa);
1690        csv (in => $fh,  out => \@aoh, bom => 1);
1691        csv (in => $fh,  out => \%hsh, key => "key");
1692
1693       In output mode, the default CSV options when producing CSV are
1694
1695        eol       => "\r\n"
1696
1697       The "fragment" attribute is ignored in output mode.
1698
1699       "out" can be a file name  (e.g.  "file.csv"),  which will be opened for
1700       writing and closed when finished,  a file handle (e.g. $fh or "FH"),  a
1701       reference to a glob (e.g. "\*STDOUT"),  the glob itself (e.g. *STDOUT),
1702       or a reference to a scalar (e.g. "\my $data").
1703
1704        csv (in => sub { $sth->fetch },            out => "dump.csv");
1705        csv (in => sub { $sth->fetchrow_hashref }, out => "dump.csv",
1706             headers => $sth->{NAME_lc});
1707
1708       When a code-ref is used for "in", the output is generated  per
1709       invocation, so no buffering is involved. This implies that there is no
1710       size restriction on the number of records. The "csv" function ends when
1711       the coderef returns a false value.
1712
1713       If "out" is set to a reference of the literal string "skip", the output
1714       will be suppressed completely,  which might be useful in combination
1715       with a filter for side effects only.
1716
1717        my %cache;
1718        csv (in    => "dump.csv",
1719             out   => \"skip",
1720             on_in => sub { $cache{$_[1][1]}++ });
1721
1722       Currently,  setting "out" to any false value  ("undef", "", 0) will be
1723       equivalent to "\"skip"".
1724
1725       If the "in" argument point to something to parse, and the "out" is set
1726       to a reference to an "ARRAY" or a "HASH", the output is appended to the
1727       data in the existing reference. The result of the parse should match
1728       what exists in the reference passed. This might come handy when you
1729       have to parse a set of files with similar content (like data stored per
1730       period) and you want to collect that into a single data structure:
1731
1732        my %hash;
1733        csv (in => $_, out => \%hash, key => "id") for sort glob "foo-[0-9]*.csv";
1734
1735        my @list; # List of arrays
1736        csv (in => $_, out => \@list)              for sort glob "foo-[0-9]*.csv";
1737
1738        my @list; # List of hashes
1739        csv (in => $_, out => \@list, bom => 1)    for sort glob "foo-[0-9]*.csv";
1740
1741       encoding
1742
1743       If passed,  it should be an encoding accepted by the  ":encoding()"
1744       option to "open". There is no default value. This attribute does not
1745       work in perl 5.6.x.  "encoding" can be abbreviated to "enc" for ease of
1746       use in command line invocations.
1747
1748       If "encoding" is set to the literal value "auto", the method "header"
1749       will be invoked on the opened stream to check if there is a BOM and set
1750       the encoding accordingly.   This is equal to passing a true value in
1751       the option "detect_bom".
1752
1753       Encodings can be stacked, as supported by "binmode":
1754
1755        # Using PerlIO::via::gzip
1756        csv (in       => \@csv,
1757             out      => "test.csv:via.gz",
1758             encoding => ":via(gzip):encoding(utf-8)",
1759             );
1760        $aoa = csv (in => "test.csv:via.gz",  encoding => ":via(gzip)");
1761
1762        # Using PerlIO::gzip
1763        csv (in       => \@csv,
1764             out      => "test.csv:via.gz",
1765             encoding => ":gzip:encoding(utf-8)",
1766             );
1767        $aoa = csv (in => "test.csv:gzip.gz", encoding => ":gzip");
1768
1769       detect_bom
1770
1771       If  "detect_bom"  is given, the method  "header"  will be invoked on
1772       the opened stream to check if there is a BOM and set the encoding
1773       accordingly.
1774
1775       "detect_bom" can be abbreviated to "bom".
1776
1777       This is the same as setting "encoding" to "auto".
1778
1779       Note that as the method  "header" is invoked,  its default is to also
1780       set the headers.
1781
1782       headers
1783
1784       If this attribute is not given, the default behavior is to produce an
1785       array of arrays.
1786
1787       If "headers" is supplied,  it should be an anonymous list of column
1788       names, an anonymous hashref, a coderef, or a literal flag:  "auto",
1789       "lc", "uc", or "skip".
1790
1791       skip
1792         When "skip" is used, the header will not be included in the output.
1793
1794          my $aoa = csv (in => $fh, headers => "skip");
1795
1796       auto
1797         If "auto" is used, the first line of the "CSV" source will be read as
1798         the list of field headers and used to produce an array of hashes.
1799
1800          my $aoh = csv (in => $fh, headers => "auto");
1801
1802       lc
1803         If "lc" is used,  the first line of the  "CSV" source will be read as
1804         the list of field headers mapped to  lower case and used to produce
1805         an array of hashes. This is a variation of "auto".
1806
1807          my $aoh = csv (in => $fh, headers => "lc");
1808
1809       uc
1810         If "uc" is used,  the first line of the  "CSV" source will be read as
1811         the list of field headers mapped to  upper case and used to produce
1812         an array of hashes. This is a variation of "auto".
1813
1814          my $aoh = csv (in => $fh, headers => "uc");
1815
1816       CODE
1817         If a coderef is used,  the first line of the  "CSV" source will be
1818         read as the list of mangled field headers in which each field is
1819         passed as the only argument to the coderef. This list is used to
1820         produce an array of hashes.
1821
1822          my $aoh = csv (in      => $fh,
1823                         headers => sub { lc ($_[0]) =~ s/kode/code/gr });
1824
1825         this example is a variation of using "lc" where all occurrences of
1826         "kode" are replaced with "code".
1827
1828       ARRAY
1829         If  "headers"  is an anonymous list,  the entries in the list will be
1830         used as field names. The first line is considered data instead of
1831         headers.
1832
1833          my $aoh = csv (in => $fh, headers => [qw( Foo Bar )]);
1834          csv (in => $aoa, out => $fh, headers => [qw( code description price )]);
1835
1836       HASH
1837         If "headers" is a hash reference, this implies "auto", but header
1838         fields that exist as key in the hashref will be replaced by the value
1839         for that key. Given a CSV file like
1840
1841          post-kode,city,name,id number,fubble
1842          1234AA,Duckstad,Donald,13,"X313DF"
1843
1844         using
1845
1846          csv (headers => { "post-kode" => "pc", "id number" => "ID" }, ...
1847
1848         will return an entry like
1849
1850          { pc     => "1234AA",
1851            city   => "Duckstad",
1852            name   => "Donald",
1853            ID     => "13",
1854            fubble => "X313DF",
1855            }
1856
1857       See also "munge_column_names" and "set_column_names".
1858
1859       munge_column_names
1860
1861       If "munge_column_names" is set,  the method  "header"  is invoked on
1862       the opened stream with all matching arguments to detect and set the
1863       headers.
1864
1865       "munge_column_names" can be abbreviated to "munge".
1866
1867       key
1868
1869       If passed,  will default  "headers"  to "auto" and return a hashref
1870       instead of an array of hashes. Allowed values are simple scalars or
1871       array-references where the first element is the joiner and the rest are
1872       the fields to join to combine the key.
1873
1874        my $ref = csv (in => "test.csv", key => "code");
1875        my $ref = csv (in => "test.csv", key => [ ":" => "code", "color" ]);
1876
1877       with test.csv like
1878
1879        code,product,price,color
1880        1,pc,850,gray
1881        2,keyboard,12,white
1882        3,mouse,5,black
1883
1884       the first example will return
1885
1886         { 1   => {
1887               code    => 1,
1888               color   => 'gray',
1889               price   => 850,
1890               product => 'pc'
1891               },
1892           2   => {
1893               code    => 2,
1894               color   => 'white',
1895               price   => 12,
1896               product => 'keyboard'
1897               },
1898           3   => {
1899               code    => 3,
1900               color   => 'black',
1901               price   => 5,
1902               product => 'mouse'
1903               }
1904           }
1905
1906       the second example will return
1907
1908         { "1:gray"    => {
1909               code    => 1,
1910               color   => 'gray',
1911               price   => 850,
1912               product => 'pc'
1913               },
1914           "2:white"   => {
1915               code    => 2,
1916               color   => 'white',
1917               price   => 12,
1918               product => 'keyboard'
1919               },
1920           "3:black"   => {
1921               code    => 3,
1922               color   => 'black',
1923               price   => 5,
1924               product => 'mouse'
1925               }
1926           }
1927
1928       The "key" attribute can be combined with "headers" for "CSV" date that
1929       has no header line, like
1930
1931        my $ref = csv (
1932            in      => "foo.csv",
1933            headers => [qw( c_foo foo bar description stock )],
1934            key     =>     "c_foo",
1935            );
1936
1937       value
1938
1939       Used to create key-value hashes.
1940
1941       Only allowed when "key" is valid. A "value" can be either a single
1942       column label or an anonymous list of column labels.  In the first case,
1943       the value will be a simple scalar value, in the latter case, it will be
1944       a hashref.
1945
1946        my $ref = csv (in => "test.csv", key   => "code",
1947                                         value => "price");
1948        my $ref = csv (in => "test.csv", key   => "code",
1949                                         value => [ "product", "price" ]);
1950        my $ref = csv (in => "test.csv", key   => [ ":" => "code", "color" ],
1951                                         value => "price");
1952        my $ref = csv (in => "test.csv", key   => [ ":" => "code", "color" ],
1953                                         value => [ "product", "price" ]);
1954
1955       with test.csv like
1956
1957        code,product,price,color
1958        1,pc,850,gray
1959        2,keyboard,12,white
1960        3,mouse,5,black
1961
1962       the first example will return
1963
1964         { 1 => 850,
1965           2 =>  12,
1966           3 =>   5,
1967           }
1968
1969       the second example will return
1970
1971         { 1   => {
1972               price   => 850,
1973               product => 'pc'
1974               },
1975           2   => {
1976               price   => 12,
1977               product => 'keyboard'
1978               },
1979           3   => {
1980               price   => 5,
1981               product => 'mouse'
1982               }
1983           }
1984
1985       the third example will return
1986
1987         { "1:gray"    => 850,
1988           "2:white"   =>  12,
1989           "3:black"   =>   5,
1990           }
1991
1992       the fourth example will return
1993
1994         { "1:gray"    => {
1995               price   => 850,
1996               product => 'pc'
1997               },
1998           "2:white"   => {
1999               price   => 12,
2000               product => 'keyboard'
2001               },
2002           "3:black"   => {
2003               price   => 5,
2004               product => 'mouse'
2005               }
2006           }
2007
2008       keep_headers
2009
2010       When using hashes,  keep the column names into the arrayref passed,  so
2011       all headers are available after the call in the original order.
2012
2013        my $aoh = csv (in => "file.csv", keep_headers => \my @hdr);
2014
2015       This attribute can be abbreviated to "kh" or passed as
2016       "keep_column_names".
2017
2018       This attribute implies a default of "auto" for the "headers" attribute.
2019
2020       fragment
2021
2022       Only output the fragment as defined in the "fragment" method. This
2023       option is ignored when generating "CSV". See "out".
2024
2025       Combining all of them could give something like
2026
2027        use Text::CSV_XS qw( csv );
2028        my $aoh = csv (
2029            in       => "test.txt",
2030            encoding => "utf-8",
2031            headers  => "auto",
2032            sep_char => "|",
2033            fragment => "row=3;6-9;15-*",
2034            );
2035        say $aoh->[15]{Foo};
2036
2037       sep_set
2038
2039       If "sep_set" is set, the method "header" is invoked on the opened
2040       stream to detect and set "sep_char" with the given set.
2041
2042       "sep_set" can be abbreviated to "seps".
2043
2044       Note that as the  "header" method is invoked,  its default is to also
2045       set the headers.
2046
2047       set_column_names
2048
2049       If  "set_column_names" is passed,  the method "header" is invoked on
2050       the opened stream with all arguments meant for "header".
2051
2052       If "set_column_names" is passed as a false value, the content of the
2053       first row is only preserved if the output is AoA:
2054
2055       With an input-file like
2056
2057        bAr,foo
2058        1,2
2059        3,4,5
2060
2061       This call
2062
2063        my $aoa = csv (in => $file, set_column_names => 0);
2064
2065       will result in
2066
2067        [[ "bar", "foo"     ],
2068         [ "1",   "2"       ],
2069         [ "3",   "4",  "5" ]]
2070
2071       and
2072
2073        my $aoa = csv (in => $file, set_column_names => 0, munge => "none");
2074
2075       will result in
2076
2077        [[ "bAr", "foo"     ],
2078         [ "1",   "2"       ],
2079         [ "3",   "4",  "5" ]]
2080
2081   Callbacks
2082       Callbacks enable actions triggered from the inside of Text::CSV_XS.
2083
2084       While most of what this enables  can easily be done in an  unrolled
2085       loop as described in the "SYNOPSIS" callbacks can be used to meet
2086       special demands or enhance the "csv" function.
2087
2088       error
2089          $csv->callbacks (error => sub { $csv->SetDiag (0) });
2090
2091         the "error"  callback is invoked when an error occurs,  but  only
2092         when "auto_diag" is set to a true value. A callback is invoked with
2093         the values returned by "error_diag":
2094
2095          my ($c, $s);
2096
2097          sub ignore3006 {
2098              my ($err, $msg, $pos, $recno, $fldno) = @_;
2099              if ($err == 3006) {
2100                  # ignore this error
2101                  ($c, $s) = (undef, undef);
2102                  Text::CSV_XS->SetDiag (0);
2103                  }
2104              # Any other error
2105              return;
2106              } # ignore3006
2107
2108          $csv->callbacks (error => \&ignore3006);
2109          $csv->bind_columns (\$c, \$s);
2110          while ($csv->getline ($fh)) {
2111              # Error 3006 will not stop the loop
2112              }
2113
2114       after_parse
2115          $csv->callbacks (after_parse => sub { push @{$_[1]}, "NEW" });
2116          while (my $row = $csv->getline ($fh)) {
2117              $row->[-1] eq "NEW";
2118              }
2119
2120         This callback is invoked after parsing with  "getline"  only if no
2121         error occurred.  The callback is invoked with two arguments:   the
2122         current "CSV" parser object and an array reference to the fields
2123         parsed.
2124
2125         The return code of the callback is ignored  unless it is a reference
2126         to the string "skip", in which case the record will be skipped in
2127         "getline_all".
2128
2129          sub add_from_db {
2130              my ($csv, $row) = @_;
2131              $sth->execute ($row->[4]);
2132              push @$row, $sth->fetchrow_array;
2133              } # add_from_db
2134
2135          my $aoa = csv (in => "file.csv", callbacks => {
2136              after_parse => \&add_from_db });
2137
2138         This hook can be used for validation:
2139
2140         FAIL
2141           Die if any of the records does not validate a rule:
2142
2143            after_parse => sub {
2144                $_[1][4] =~ m/^[0-9]{4}\s?[A-Z]{2}$/ or
2145                    die "5th field does not have a valid Dutch zipcode";
2146                }
2147
2148         DEFAULT
2149           Replace invalid fields with a default value:
2150
2151            after_parse => sub { $_[1][2] =~ m/^\d+$/ or $_[1][2] = 0 }
2152
2153         SKIP
2154           Skip records that have invalid fields (only applies to
2155           "getline_all"):
2156
2157            after_parse => sub { $_[1][0] =~ m/^\d+$/ or return \"skip"; }
2158
2159       before_print
2160          my $idx = 1;
2161          $csv->callbacks (before_print => sub { $_[1][0] = $idx++ });
2162          $csv->print (*STDOUT, [ 0, $_ ]) for @members;
2163
2164         This callback is invoked  before printing with  "print"  only if no
2165         error occurred.  The callback is invoked with two arguments:  the
2166         current  "CSV" parser object and an array reference to the fields
2167         passed.
2168
2169         The return code of the callback is ignored.
2170
2171          sub max_4_fields {
2172              my ($csv, $row) = @_;
2173              @$row > 4 and splice @$row, 4;
2174              } # max_4_fields
2175
2176          csv (in => csv (in => "file.csv"), out => *STDOUT,
2177              callbacks => { before_print => \&max_4_fields });
2178
2179         This callback is not active for "combine".
2180
2181       Callbacks for csv ()
2182
2183       The "csv" allows for some callbacks that do not integrate in XS
2184       internals but only feature the "csv" function.
2185
2186         csv (in        => "file.csv",
2187              callbacks => {
2188                  filter       => { 6 => sub { $_ > 15 } },    # first
2189                  after_parse  => sub { say "AFTER PARSE";  }, # first
2190                  after_in     => sub { say "AFTER IN";     }, # second
2191                  on_in        => sub { say "ON IN";        }, # third
2192                  },
2193              );
2194
2195         csv (in        => $aoh,
2196              out       => "file.csv",
2197              callbacks => {
2198                  on_in        => sub { say "ON IN";        }, # first
2199                  before_out   => sub { say "BEFORE OUT";   }, # second
2200                  before_print => sub { say "BEFORE PRINT"; }, # third
2201                  },
2202              );
2203
2204       filter
2205         This callback can be used to filter records.  It is called just after
2206         a new record has been scanned.  The callback accepts a:
2207
2208         hashref
2209           The keys are the index to the row (the field name or field number,
2210           1-based) and the values are subs to return a true or false value.
2211
2212            csv (in => "file.csv", filter => {
2213                       3 => sub { m/a/ },       # third field should contain an "a"
2214                       5 => sub { length > 4 }, # length of the 5th field minimal 5
2215                       });
2216
2217            csv (in => "file.csv", filter => { foo => sub { $_ > 4 }});
2218
2219           If the keys to the filter hash contain any character that is not a
2220           digit it will also implicitly set "headers" to "auto"  unless
2221           "headers"  was already passed as argument.  When headers are
2222           active, returning an array of hashes, the filter is not applicable
2223           to the header itself.
2224
2225           All sub results should match, as in AND.
2226
2227           The context of the callback sets  $_ localized to the field
2228           indicated by the filter. The two arguments are as with all other
2229           callbacks, so the other fields in the current row can be seen:
2230
2231            filter => { 3 => sub { $_ > 100 ? $_[1][1] =~ m/A/ : $_[1][6] =~ m/B/ }}
2232
2233           If the context is set to return a list of hashes  ("headers" is
2234           defined), the current record will also be available in the
2235           localized %_:
2236
2237            filter => { 3 => sub { $_ > 100 && $_{foo} =~ m/A/ && $_{bar} < 1000  }}
2238
2239           If the filter is used to alter the content by changing $_,  make
2240           sure that the sub returns true in order not to have that record
2241           skipped:
2242
2243            filter => { 2 => sub { $_ = uc }}
2244
2245           will upper-case the second field, and then skip it if the resulting
2246           content evaluates to false. To always accept, end with truth:
2247
2248            filter => { 2 => sub { $_ = uc; 1 }}
2249
2250         coderef
2251            csv (in => "file.csv", filter => sub { $n++; 0; });
2252
2253           If the argument to "filter" is a coderef,  it is an alias or
2254           shortcut to a filter on column 0:
2255
2256            csv (filter => sub { $n++; 0 });
2257
2258           is equal to
2259
2260            csv (filter => { 0 => sub { $n++; 0 });
2261
2262         filter-name
2263            csv (in => "file.csv", filter => "not_blank");
2264            csv (in => "file.csv", filter => "not_empty");
2265            csv (in => "file.csv", filter => "filled");
2266
2267           These are predefined filters
2268
2269           Given a file like (line numbers prefixed for doc purpose only):
2270
2271            1:1,2,3
2272            2:
2273            3:,
2274            4:""
2275            5:,,
2276            6:, ,
2277            7:"",
2278            8:" "
2279            9:4,5,6
2280
2281           not_blank
2282             Filter out the blank lines
2283
2284             This filter is a shortcut for
2285
2286              filter => { 0 => sub { @{$_[1]} > 1 or
2287                          defined $_[1][0] && $_[1][0] ne "" } }
2288
2289             Due to the implementation,  it is currently impossible to also
2290             filter lines that consists only of a quoted empty field. These
2291             lines are also considered blank lines.
2292
2293             With the given example, lines 2 and 4 will be skipped.
2294
2295           not_empty
2296             Filter out lines where all the fields are empty.
2297
2298             This filter is a shortcut for
2299
2300              filter => { 0 => sub { grep { defined && $_ ne "" } @{$_[1]} } }
2301
2302             A space is not regarded being empty, so given the example data,
2303             lines 2, 3, 4, 5, and 7 are skipped.
2304
2305           filled
2306             Filter out lines that have no visible data
2307
2308             This filter is a shortcut for
2309
2310              filter => { 0 => sub { grep { defined && m/\S/ } @{$_[1]} } }
2311
2312             This filter rejects all lines that not have at least one field
2313             that does not evaluate to the empty string.
2314
2315             With the given example data, this filter would skip lines 2
2316             through 8.
2317
2318         One could also use modules like Types::Standard:
2319
2320          use Types::Standard -types;
2321
2322          my $type   = Tuple[Str, Str, Int, Bool, Optional[Num]];
2323          my $check  = $type->compiled_check;
2324
2325          # filter with compiled check and warnings
2326          my $aoa = csv (
2327             in     => \$data,
2328             filter => {
2329                 0 => sub {
2330                     my $ok = $check->($_[1]) or
2331                         warn $type->get_message ($_[1]), "\n";
2332                     return $ok;
2333                     },
2334                 },
2335             );
2336
2337       after_in
2338         This callback is invoked for each record after all records have been
2339         parsed but before returning the reference to the caller.  The hook is
2340         invoked with two arguments:  the current  "CSV"  parser object  and a
2341         reference to the record.   The reference can be a reference to a
2342         HASH  or a reference to an ARRAY as determined by the arguments.
2343
2344         This callback can also be passed as  an attribute without the
2345         "callbacks" wrapper.
2346
2347       before_out
2348         This callback is invoked for each record before the record is
2349         printed.  The hook is invoked with two arguments:  the current "CSV"
2350         parser object and a reference to the record.   The reference can be a
2351         reference to a  HASH or a reference to an ARRAY as determined by the
2352         arguments.
2353
2354         This callback can also be passed as an attribute  without the
2355         "callbacks" wrapper.
2356
2357         This callback makes the row available in %_ if the row is a hashref.
2358         In this case %_ is writable and will change the original row.
2359
2360       on_in
2361         This callback acts exactly as the "after_in" or the "before_out"
2362         hooks.
2363
2364         This callback can also be passed as an attribute  without the
2365         "callbacks" wrapper.
2366
2367         This callback makes the row available in %_ if the row is a hashref.
2368         In this case %_ is writable and will change the original row. So e.g.
2369         with
2370
2371           my $aoh = csv (
2372               in      => \"foo\n1\n2\n",
2373               headers => "auto",
2374               on_in   => sub { $_{bar} = 2; },
2375               );
2376
2377         $aoh will be:
2378
2379           [ { foo => 1,
2380               bar => 2,
2381               }
2382             { foo => 2,
2383               bar => 2,
2384               }
2385             ]
2386
2387       csv
2388         The function  "csv" can also be called as a method or with an
2389         existing Text::CSV_XS object. This could help if the function is to
2390         be invoked a lot of times and the overhead of creating the object
2391         internally over  and  over again would be prevented by passing an
2392         existing instance.
2393
2394          my $csv = Text::CSV_XS->new ({ binary => 1, auto_diag => 1 });
2395
2396          my $aoa = $csv->csv (in => $fh);
2397          my $aoa = csv (in => $fh, csv => $csv);
2398
2399         both act the same. Running this 20000 times on a 20 lines CSV file,
2400         showed a 53% speedup.
2401

INTERNALS

2403       Combine (...)
2404       Parse (...)
2405
2406       The arguments to these internal functions are deliberately not
2407       described or documented in order to enable the  module authors make
2408       changes it when they feel the need for it.  Using them is  highly
2409       discouraged  as  the  API may change in future releases.
2410

EXAMPLES

2412   Reading a CSV file line by line:
2413        my $csv = Text::CSV_XS->new ({ binary => 1, auto_diag => 1 });
2414        open my $fh, "<", "file.csv" or die "file.csv: $!";
2415        while (my $row = $csv->getline ($fh)) {
2416            # do something with @$row
2417            }
2418        close $fh or die "file.csv: $!";
2419
2420       or
2421
2422        my $aoa = csv (in => "file.csv", on_in => sub {
2423            # do something with %_
2424            });
2425
2426       Reading only a single column
2427
2428        my $csv = Text::CSV_XS->new ({ binary => 1, auto_diag => 1 });
2429        open my $fh, "<", "file.csv" or die "file.csv: $!";
2430        # get only the 4th column
2431        my @column = map { $_->[3] } @{$csv->getline_all ($fh)};
2432        close $fh or die "file.csv: $!";
2433
2434       with "csv", you could do
2435
2436        my @column = map { $_->[0] }
2437            @{csv (in => "file.csv", fragment => "col=4")};
2438
2439   Parsing CSV strings:
2440        my $csv = Text::CSV_XS->new ({ keep_meta_info => 1, binary => 1 });
2441
2442        my $sample_input_string =
2443            qq{"I said, ""Hi!""",Yes,"",2.34,,"1.09","\x{20ac}",};
2444        if ($csv->parse ($sample_input_string)) {
2445            my @field = $csv->fields;
2446            foreach my $col (0 .. $#field) {
2447                my $quo = $csv->is_quoted ($col) ? $csv->{quote_char} : "";
2448                printf "%2d: %s%s%s\n", $col, $quo, $field[$col], $quo;
2449                }
2450            }
2451        else {
2452            print STDERR "parse () failed on argument: ",
2453                $csv->error_input, "\n";
2454            $csv->error_diag ();
2455            }
2456
2457       Parsing CSV from memory
2458
2459       Given a complete CSV data-set in scalar $data,  generate a list of
2460       lists to represent the rows and fields
2461
2462        # The data
2463        my $data = join "\r\n" => map { join "," => 0 .. 5 } 0 .. 5;
2464
2465        # in a loop
2466        my $csv = Text::CSV_XS->new ({ binary => 1, auto_diag => 1 });
2467        open my $fh, "<", \$data;
2468        my @foo;
2469        while (my $row = $csv->getline ($fh)) {
2470            push @foo, $row;
2471            }
2472        close $fh;
2473
2474        # a single call
2475        my $foo = csv (in => \$data);
2476
2477   Printing CSV data
2478       The fast way: using "print"
2479
2480       An example for creating "CSV" files using the "print" method:
2481
2482        my $csv = Text::CSV_XS->new ({ binary => 1, eol => $/ });
2483        open my $fh, ">", "foo.csv" or die "foo.csv: $!";
2484        for (1 .. 10) {
2485            $csv->print ($fh, [ $_, "$_" ]) or $csv->error_diag;
2486            }
2487        close $fh or die "$tbl.csv: $!";
2488
2489       The slow way: using "combine" and "string"
2490
2491       or using the slower "combine" and "string" methods:
2492
2493        my $csv = Text::CSV_XS->new;
2494
2495        open my $csv_fh, ">", "hello.csv" or die "hello.csv: $!";
2496
2497        my @sample_input_fields = (
2498            'You said, "Hello!"',   5.67,
2499            '"Surely"',   '',   '3.14159');
2500        if ($csv->combine (@sample_input_fields)) {
2501            print $csv_fh $csv->string, "\n";
2502            }
2503        else {
2504            print "combine () failed on argument: ",
2505                $csv->error_input, "\n";
2506            }
2507        close $csv_fh or die "hello.csv: $!";
2508
2509       Generating CSV into memory
2510
2511       Format a data-set (@foo) into a scalar value in memory ($data):
2512
2513        # The data
2514        my @foo = map { [ 0 .. 5 ] } 0 .. 3;
2515
2516        # in a loop
2517        my $csv = Text::CSV_XS->new ({ binary => 1, auto_diag => 1, eol => "\r\n" });
2518        open my $fh, ">", \my $data;
2519        $csv->print ($fh, $_) for @foo;
2520        close $fh;
2521
2522        # a single call
2523        csv (in => \@foo, out => \my $data);
2524
2525   Rewriting CSV
2526       Rewrite "CSV" files with ";" as separator character to well-formed
2527       "CSV":
2528
2529        use Text::CSV_XS qw( csv );
2530        csv (in => csv (in => "bad.csv", sep_char => ";"), out => *STDOUT);
2531
2532       As "STDOUT" is now default in "csv", a one-liner converting a UTF-16
2533       CSV file with BOM and TAB-separation to valid UTF-8 CSV could be:
2534
2535        $ perl -C3 -MText::CSV_XS=csv -we\
2536           'csv(in=>"utf16tab.csv",encoding=>"utf16",sep=>"\t")' >utf8.csv
2537
2538   Dumping database tables to CSV
2539       Dumping a database table can be simple as this (TIMTOWTDI):
2540
2541        my $dbh = DBI->connect (...);
2542        my $sql = "select * from foo";
2543
2544        # using your own loop
2545        open my $fh, ">", "foo.csv" or die "foo.csv: $!\n";
2546        my $csv = Text::CSV_XS->new ({ binary => 1, eol => "\r\n" });
2547        my $sth = $dbh->prepare ($sql); $sth->execute;
2548        $csv->print ($fh, $sth->{NAME_lc});
2549        while (my $row = $sth->fetch) {
2550            $csv->print ($fh, $row);
2551            }
2552
2553        # using the csv function, all in memory
2554        csv (out => "foo.csv", in => $dbh->selectall_arrayref ($sql));
2555
2556        # using the csv function, streaming with callbacks
2557        my $sth = $dbh->prepare ($sql); $sth->execute;
2558        csv (out => "foo.csv", in => sub { $sth->fetch            });
2559        csv (out => "foo.csv", in => sub { $sth->fetchrow_hashref });
2560
2561       Note that this does not discriminate between "empty" values and NULL-
2562       values from the database,  as both will be the same empty field in CSV.
2563       To enable distinction between the two, use "quote_empty".
2564
2565        csv (out => "foo.csv", in => sub { $sth->fetch }, quote_empty => 1);
2566
2567       If the database import utility supports special sequences to insert
2568       "NULL" values into the database,  like MySQL/MariaDB supports "\N",
2569       use a filter or a map
2570
2571        csv (out => "foo.csv", in => sub { $sth->fetch },
2572                            on_in => sub { $_ //= "\\N" for @{$_[1]} });
2573
2574        while (my $row = $sth->fetch) {
2575            $csv->print ($fh, [ map { $_ // "\\N" } @$row ]);
2576            }
2577
2578       Note that this will not work as expected when choosing the backslash
2579       ("\") as "escape_char", as that will cause the "\" to need to be
2580       escaped by yet another "\",  which will cause the field to need
2581       quotation and thus ending up as "\\N" instead of "\N". See also
2582       "undef_str".
2583
2584        csv (out => "foo.csv", in => sub { $sth->fetch }, undef_str => "\\N");
2585
2586       These special sequences are not recognized by  Text::CSV_XS  on parsing
2587       the CSV generated like this, but map and filter are your friends again
2588
2589        while (my $row = $csv->getline ($fh)) {
2590            $sth->execute (map { $_ eq "\\N" ? undef : $_ } @$row);
2591            }
2592
2593        csv (in => "foo.csv", filter => { 1 => sub {
2594            $sth->execute (map { $_ eq "\\N" ? undef : $_ } @{$_[1]}); 0; }});
2595
2596   The examples folder
2597       For more extended examples, see the examples/ 1. sub-directory in the
2598       original distribution or the git repository 2.
2599
2600        1. https://github.com/Tux/Text-CSV_XS/tree/master/examples
2601        2. https://github.com/Tux/Text-CSV_XS
2602
2603       The following files can be found there:
2604
2605       parser-xs.pl
2606         This can be used as a boilerplate to parse invalid "CSV"  and parse
2607         beyond (expected) errors alternative to using the "error" callback.
2608
2609          $ perl examples/parser-xs.pl bad.csv >good.csv
2610
2611       csv-check
2612         This is a command-line tool that uses parser-xs.pl  techniques to
2613         check the "CSV" file and report on its content.
2614
2615          $ csv-check files/utf8.csv
2616          Checked files/utf8.csv  with csv-check 1.9
2617          using Text::CSV_XS 1.32 with perl 5.26.0 and Unicode 9.0.0
2618          OK: rows: 1, columns: 2
2619              sep = <,>, quo = <">, bin = <1>, eol = <"\n">
2620
2621       csv-split
2622         This command splits "CSV" files into smaller files,  keeping (part
2623         of) the header.  Options include maximum number of (data) rows per
2624         file and maximum number of columns per file or a combination of the
2625         two.
2626
2627       csv2xls
2628         A script to convert "CSV" to Microsoft Excel ("XLS"). This requires
2629         extra modules Date::Calc and Spreadsheet::WriteExcel. The converter
2630         accepts various options and can produce UTF-8 compliant Excel files.
2631
2632       csv2xlsx
2633         A script to convert "CSV" to Microsoft Excel ("XLSX").  This requires
2634         the modules Date::Calc and Spreadsheet::Writer::XLSX.  The converter
2635         does accept various options including merging several "CSV" files
2636         into a single Excel file.
2637
2638       csvdiff
2639         A script that provides colorized diff on sorted CSV files,  assuming
2640         first line is header and first field is the key. Output options
2641         include colorized ANSI escape codes or HTML.
2642
2643          $ csvdiff --html --output=diff.html file1.csv file2.csv
2644
2645       rewrite.pl
2646         A script to rewrite (in)valid CSV into valid CSV files.  Script has
2647         options to generate confusing CSV files or CSV files that conform to
2648         Dutch MS-Excel exports (using ";" as separation).
2649
2650         Script - by default - honors BOM  and auto-detects separation
2651         converting it to default standard CSV with "," as separator.
2652

CAVEATS

2654       Text::CSV_XS  is not designed to detect the characters used to quote
2655       and separate fields.  The parsing is done using predefined  (default)
2656       settings.  In the examples  sub-directory,  you can find scripts  that
2657       demonstrate how you could try to detect these characters yourself.
2658
2659   Microsoft Excel
2660       The import/export from Microsoft Excel is a risky task, according to
2661       the documentation in "Text::CSV::Separator".  Microsoft uses the
2662       system's list separator defined in the regional settings, which happens
2663       to be a semicolon for Dutch, German and Spanish (and probably some
2664       others as well).   For the English locale,  the default is a comma.
2665       In Windows however,  the user is free to choose a  predefined locale,
2666       and then change  every  individual setting in it, so checking the
2667       locale is no solution.
2668
2669       As of version 1.17, a lone first line with just
2670
2671         sep=;
2672
2673       will be recognized and honored when parsing with "getline".
2674

TODO

2676       More Errors & Warnings
2677         New extensions ought to be  clear and concise  in reporting what
2678         error has occurred where and why, and maybe also offer a remedy to
2679         the problem.
2680
2681         "error_diag" is a (very) good start, but there is more work to be
2682         done in this area.
2683
2684         Basic calls  should croak or warn on  illegal parameters.  Errors
2685         should be documented.
2686
2687       setting meta info
2688         Future extensions might include extending the "meta_info",
2689         "is_quoted", and  "is_binary"  to accept setting these  flags for
2690         fields,  so you can specify which fields are quoted in the
2691         "combine"/"string" combination.
2692
2693          $csv->meta_info (0, 1, 1, 3, 0, 0);
2694          $csv->is_quoted (3, 1);
2695
2696         Metadata Vocabulary for Tabular Data
2697         <http://w3c.github.io/csvw/metadata/> (a W3C editor's draft) could be
2698         an example for supporting more metadata.
2699
2700       Parse the whole file at once
2701         Implement new methods or functions  that enable parsing of a
2702         complete file at once, returning a list of hashes. Possible extension
2703         to this could be to enable a column selection on the call:
2704
2705          my @AoH = $csv->parse_file ($filename, { cols => [ 1, 4..8, 12 ]});
2706
2707         returning something like
2708
2709          [ { fields => [ 1, 2, "foo", 4.5, undef, "", 8 ],
2710              flags  => [ ... ],
2711              },
2712            { fields => [ ... ],
2713              .
2714              },
2715            ]
2716
2717         Note that the "csv" function already supports most of this,  but does
2718         not return flags. "getline_all" returns all rows for an open stream,
2719         but this will not return flags either.  "fragment"  can reduce the
2720         required  rows or columns, but cannot combine them.
2721
2722       Cookbook
2723         Write a document that has recipes for  most known  non-standard  (and
2724         maybe some standard)  "CSV" formats,  including formats that use
2725         "TAB",  ";", "|", or other non-comma separators.
2726
2727         Examples could be taken from W3C's CSV on the Web: Use Cases and
2728         Requirements <http://w3c.github.io/csvw/use-cases-and-
2729         requirements/index.html>
2730
2731       Steal
2732         Steal good new ideas and features from PapaParse
2733         <http://papaparse.com> or csvkit <http://csvkit.readthedocs.org>.
2734
2735       Perl6 support
2736         I'm already working on perl6 support here
2737         <https://github.com/Tux/CSV>. No promises yet on when it is finished
2738         (or fast). Trying to keep the API alike as much as possible.
2739
2740   NOT TODO
2741       combined methods
2742         Requests for adding means (methods) that combine "combine" and
2743         "string" in a single call will not be honored (use "print" instead).
2744         Likewise for "parse" and "fields"  (use "getline" instead), given the
2745         problems with embedded newlines.
2746
2747   Release plan
2748       No guarantees, but this is what I had in mind some time ago:
2749
2750       • DIAGNOSTICS section in pod to *describe* the errors (see below)
2751

EBCDIC

2753       Everything should now work on native EBCDIC systems.   As the test does
2754       not cover all possible codepoints and Encode does not support
2755       "utf-ebcdic", there is no guarantee that all handling of Unicode is
2756       done correct.
2757
2758       Opening "EBCDIC" encoded files on  "ASCII"+  systems is likely to
2759       succeed using Encode's "cp37", "cp1047", or "posix-bc":
2760
2761        open my $fh, "<:encoding(cp1047)", "ebcdic_file.csv" or die "...";
2762

DIAGNOSTICS

2764       Still under construction ...
2765
2766       If an error occurs,  "$csv->error_diag" can be used to get information
2767       on the cause of the failure. Note that for speed reasons the internal
2768       value is never cleared on success,  so using the value returned by
2769       "error_diag" in normal cases - when no error occurred - may cause
2770       unexpected results.
2771
2772       If the constructor failed, the cause can be found using "error_diag" as
2773       a class method, like "Text::CSV_XS->error_diag".
2774
2775       The "$csv->error_diag" method is automatically invoked upon error when
2776       the contractor was called with  "auto_diag"  set to  1 or 2, or when
2777       autodie is in effect.  When set to 1, this will cause a "warn" with the
2778       error message,  when set to 2, it will "die". "2012 - EOF" is excluded
2779       from "auto_diag" reports.
2780
2781       Errors can be (individually) caught using the "error" callback.
2782
2783       The errors as described below are available. I have tried to make the
2784       error itself explanatory enough, but more descriptions will be added.
2785       For most of these errors, the first three capitals describe the error
2786       category:
2787
2788       • INI
2789
2790         Initialization error or option conflict.
2791
2792       • ECR
2793
2794         Carriage-Return related parse error.
2795
2796       • EOF
2797
2798         End-Of-File related parse error.
2799
2800       • EIQ
2801
2802         Parse error inside quotation.
2803
2804       • EIF
2805
2806         Parse error inside field.
2807
2808       • ECB
2809
2810         Combine error.
2811
2812       • EHR
2813
2814         HashRef parse related error.
2815
2816       And below should be the complete list of error codes that can be
2817       returned:
2818
2819       • 1001 "INI - sep_char is equal to quote_char or escape_char"
2820
2821         The  separation character  cannot be equal to  the quotation
2822         character or to the escape character,  as this would invalidate all
2823         parsing rules.
2824
2825       • 1002 "INI - allow_whitespace with escape_char or quote_char SP or
2826         TAB"
2827
2828         Using the  "allow_whitespace"  attribute  when either "quote_char" or
2829         "escape_char"  is equal to "SPACE" or "TAB" is too ambiguous to
2830         allow.
2831
2832       • 1003 "INI - \r or \n in main attr not allowed"
2833
2834         Using default "eol" characters in either "sep_char", "quote_char",
2835         or  "escape_char"  is  not allowed.
2836
2837       • 1004 "INI - callbacks should be undef or a hashref"
2838
2839         The "callbacks"  attribute only allows one to be "undef" or a hash
2840         reference.
2841
2842       • 1005 "INI - EOL too long"
2843
2844         The value passed for EOL is exceeding its maximum length (16).
2845
2846       • 1006 "INI - SEP too long"
2847
2848         The value passed for SEP is exceeding its maximum length (16).
2849
2850       • 1007 "INI - QUOTE too long"
2851
2852         The value passed for QUOTE is exceeding its maximum length (16).
2853
2854       • 1008 "INI - SEP undefined"
2855
2856         The value passed for SEP should be defined and not empty.
2857
2858       • 1010 "INI - the header is empty"
2859
2860         The header line parsed in the "header" is empty.
2861
2862       • 1011 "INI - the header contains more than one valid separator"
2863
2864         The header line parsed in the  "header"  contains more than one
2865         (unique) separator character out of the allowed set of separators.
2866
2867       • 1012 "INI - the header contains an empty field"
2868
2869         The header line parsed in the "header" contains an empty field.
2870
2871       • 1013 "INI - the header contains nun-unique fields"
2872
2873         The header line parsed in the  "header"  contains at least  two
2874         identical fields.
2875
2876       • 1014 "INI - header called on undefined stream"
2877
2878         The header line cannot be parsed from an undefined source.
2879
2880       • 1500 "PRM - Invalid/unsupported argument(s)"
2881
2882         Function or method called with invalid argument(s) or parameter(s).
2883
2884       • 1501 "PRM - The key attribute is passed as an unsupported type"
2885
2886         The "key" attribute is of an unsupported type.
2887
2888       • 1502 "PRM - The value attribute is passed without the key attribute"
2889
2890         The "value" attribute is only allowed when a valid key is given.
2891
2892       • 1503 "PRM - The value attribute is passed as an unsupported type"
2893
2894         The "value" attribute is of an unsupported type.
2895
2896       • 2010 "ECR - QUO char inside quotes followed by CR not part of EOL"
2897
2898         When  "eol"  has  been  set  to  anything  but the  default,  like
2899         "\r\t\n",  and  the  "\r"  is  following  the   second   (closing)
2900         "quote_char", where the characters following the "\r" do not make up
2901         the "eol" sequence, this is an error.
2902
2903       • 2011 "ECR - Characters after end of quoted field"
2904
2905         Sequences like "1,foo,"bar"baz,22,1" are not allowed. "bar" is a
2906         quoted field and after the closing double-quote, there should be
2907         either a new-line sequence or a separation character.
2908
2909       • 2012 "EOF - End of data in parsing input stream"
2910
2911         Self-explaining. End-of-file while inside parsing a stream. Can
2912         happen only when reading from streams with "getline",  as using
2913         "parse" is done on strings that are not required to have a trailing
2914         "eol".
2915
2916       • 2013 "INI - Specification error for fragments RFC7111"
2917
2918         Invalid specification for URI "fragment" specification.
2919
2920       • 2014 "ENF - Inconsistent number of fields"
2921
2922         Inconsistent number of fields under strict parsing.
2923
2924       • 2021 "EIQ - NL char inside quotes, binary off"
2925
2926         Sequences like "1,"foo\nbar",22,1" are allowed only when the binary
2927         option has been selected with the constructor.
2928
2929       • 2022 "EIQ - CR char inside quotes, binary off"
2930
2931         Sequences like "1,"foo\rbar",22,1" are allowed only when the binary
2932         option has been selected with the constructor.
2933
2934       • 2023 "EIQ - QUO character not allowed"
2935
2936         Sequences like ""foo "bar" baz",qu" and "2023,",2008-04-05,"Foo,
2937         Bar",\n" will cause this error.
2938
2939       • 2024 "EIQ - EOF cannot be escaped, not even inside quotes"
2940
2941         The escape character is not allowed as last character in an input
2942         stream.
2943
2944       • 2025 "EIQ - Loose unescaped escape"
2945
2946         An escape character should escape only characters that need escaping.
2947
2948         Allowing  the escape  for other characters  is possible  with the
2949         attribute "allow_loose_escapes".
2950
2951       • 2026 "EIQ - Binary character inside quoted field, binary off"
2952
2953         Binary characters are not allowed by default.    Exceptions are
2954         fields that contain valid UTF-8,  that will automatically be upgraded
2955         if the content is valid UTF-8. Set "binary" to 1 to accept binary
2956         data.
2957
2958       • 2027 "EIQ - Quoted field not terminated"
2959
2960         When parsing a field that started with a quotation character,  the
2961         field is expected to be closed with a quotation character.   When the
2962         parsed line is exhausted before the quote is found, that field is not
2963         terminated.
2964
2965       • 2030 "EIF - NL char inside unquoted verbatim, binary off"
2966
2967       • 2031 "EIF - CR char is first char of field, not part of EOL"
2968
2969       • 2032 "EIF - CR char inside unquoted, not part of EOL"
2970
2971       • 2034 "EIF - Loose unescaped quote"
2972
2973       • 2035 "EIF - Escaped EOF in unquoted field"
2974
2975       • 2036 "EIF - ESC error"
2976
2977       • 2037 "EIF - Binary character in unquoted field, binary off"
2978
2979       • 2110 "ECB - Binary character in Combine, binary off"
2980
2981       • 2200 "EIO - print to IO failed. See errno"
2982
2983       • 3001 "EHR - Unsupported syntax for column_names ()"
2984
2985       • 3002 "EHR - getline_hr () called before column_names ()"
2986
2987       • 3003 "EHR - bind_columns () and column_names () fields count
2988         mismatch"
2989
2990       • 3004 "EHR - bind_columns () only accepts refs to scalars"
2991
2992       • 3006 "EHR - bind_columns () did not pass enough refs for parsed
2993         fields"
2994
2995       • 3007 "EHR - bind_columns needs refs to writable scalars"
2996
2997       • 3008 "EHR - unexpected error in bound fields"
2998
2999       • 3009 "EHR - print_hr () called before column_names ()"
3000
3001       • 3010 "EHR - print_hr () called with invalid arguments"
3002

SEE ALSO

3004       IO::File,  IO::Handle,  IO::Wrap,  Text::CSV,  Text::CSV_PP,
3005       Text::CSV::Encoded,     Text::CSV::Separator,    Text::CSV::Slurp,
3006       Spreadsheet::CSV and Spreadsheet::Read, and of course perl.
3007
3008       If you are using perl6,  you can have a look at  "Text::CSV"  in the
3009       perl6 ecosystem, offering the same features.
3010
3011       non-perl
3012
3013       A CSV parser in JavaScript,  also used by W3C <http://www.w3.org>,  is
3014       the multi-threaded in-browser PapaParse <http://papaparse.com/>.
3015
3016       csvkit <http://csvkit.readthedocs.org> is a python CSV parsing toolkit.
3017

AUTHOR

3019       Alan Citterman <alan@mfgrtl.com> wrote the original Perl module.
3020       Please don't send mail concerning Text::CSV_XS to Alan, who is not
3021       involved in the C/XS part that is now the main part of the module.
3022
3023       Jochen Wiedmann <joe@ispsoft.de> rewrote the en- and decoding in C by
3024       implementing a simple finite-state machine.   He added variable quote,
3025       escape and separator characters, the binary mode and the print and
3026       getline methods. See ChangeLog releases 0.10 through 0.23.
3027
3028       H.Merijn Brand <h.m.brand@xs4all.nl> cleaned up the code,  added the
3029       field flags methods,  wrote the major part of the test suite, completed
3030       the documentation,   fixed most RT bugs,  added all the allow flags and
3031       the "csv" function. See ChangeLog releases 0.25 and on.
3032
3034        Copyright (C) 2007-2021 H.Merijn Brand.  All rights reserved.
3035        Copyright (C) 1998-2001 Jochen Wiedmann. All rights reserved.
3036        Copyright (C) 1997      Alan Citterman.  All rights reserved.
3037
3038       This library is free software;  you can redistribute and/or modify it
3039       under the same terms as Perl itself.
3040
3041
3042
3043perl v5.32.1                      2021-03-24                         CSV_XS(3)
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