1MARC::Batch(3) User Contributed Perl Documentation MARC::Batch(3)
2
3
4
6 MARC::Batch - Perl module for handling files of MARC::Record objects
7
9 MARC::Batch hides all the file handling of files of "MARC::Record"s.
10 "MARC::Record" still does the file I/O, but "MARC::Batch" handles the
11 multiple-file aspects.
12
13 use MARC::Batch;
14
15 # If you have weird control fields...
16 use MARC::Field;
17 MARC::Field->allow_controlfield_tags('FMT', 'LDX');
18
19
20 my $batch = MARC::Batch->new( 'USMARC', @files );
21 while ( my $marc = $batch->next ) {
22 print $marc->subfield(245,"a"), "\n";
23 }
24
26 None. Everything is a class method.
27
29 new( $type, @files )
30 Create a "MARC::Batch" object that will process @files.
31
32 $type must be either "USMARC" or "MicroLIF". If you want to specify
33 "MARC::File::USMARC" or "MARC::File::MicroLIF", that's OK, too. "new()"
34 returns a new MARC::Batch object.
35
36 @files can be a list of filenames:
37
38 my $batch = MARC::Batch->new( 'USMARC', 'file1.marc', 'file2.marc' );
39
40 Your @files may also contain filehandles. So if you've got a large file
41 that's gzipped you can open a pipe to gzip and pass it in:
42
43 my $fh = IO::File->new( 'gunzip -c marc.dat.gz |' );
44 my $batch = MARC::Batch->new( 'USMARC', $fh );
45
46 And you can mix and match if you really want to:
47
48 my $batch = MARC::Batch->new( 'USMARC', $fh, 'file1.marc' );
49
50 next()
51 Read the next record from that batch, and return it as a MARC::Record
52 object. If the current file is at EOF, close it and open the next one.
53 "next()" will return "undef" when there is no more data to be read from
54 any batch files.
55
56 By default, "next()" also will return "undef" if an error is
57 encountered while reading from the batch. If not checked for this can
58 cause your iteration to terminate prematurely. To alter this behavior,
59 see "strict_off()". You can retrieve warning messages using the
60 "warnings()" method.
61
62 Optionally you can pass in a filter function as a subroutine reference
63 if you are only interested in particular fields from the record. This
64 can boost performance.
65
66 strict_off()
67 If you would like "MARC::Batch" to continue after it has encountered
68 what it believes to be bad MARC data then use this method to turn
69 strict OFF. A call to "strict_off()" always returns true (1).
70
71 "strict_off()" can be handy when you don't care about the quality of
72 your MARC data, and just want to plow through it. For safety,
73 "MARC::Batch" strict is ON by default.
74
75 strict_on()
76 The opposite of "strict_off()", and the default state. You shouldn't
77 have to use this method unless you've previously used "strict_off()",
78 and want it back on again. When strict is ON calls to next() will
79 return undef when an error is encountered while reading MARC data.
80 strict_on() always returns true (1).
81
82 warnings()
83 Returns a list of warnings that have accumulated while processing a
84 particular batch file. As a side effect the warning buffer will be
85 cleared.
86
87 my @warnings = $batch->warnings();
88
89 This method is also used internally to set warnings, so you probably
90 don't want to be passing in anything as this will set warnings on your
91 batch object.
92
93 "warnings()" will return the empty list when there are no warnings.
94
95 warnings_off()
96 Turns off the default behavior of printing warnings to STDERR. However,
97 even with warnings off the messages can still be retrieved using the
98 warnings() method if you wish to check for them.
99
100 "warnings_off()" always returns true (1).
101
102 warnings_on()
103 Turns on warnings so that diagnostic information is printed to STDERR.
104 This is on by default so you shouldn't have to use it unless you've
105 previously turned off warnings using warnings_off().
106
107 warnings_on() always returns true (1).
108
109 filename()
110 Returns the currently open filename or "undef" if there is not
111 currently a file open on this batch object.
112
114 MARC::Record, MARC::Lint
115
117 None yet. Send me your ideas and needs.
118
120 This code may be distributed under the same terms as Perl itself.
121
122 Please note that these modules are not products of or supported by the
123 employers of the various contributors to the code.
124
126 Andy Lester, "<andy@petdance.com>"
127
128
129
130perl v5.34.0 2022-01-21 MARC::Batch(3)