1Pod::Checker(3pm)      Perl Programmers Reference Guide      Pod::Checker(3pm)
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3
4

NAME

6       Pod::Checker, podchecker() - check pod documents for syntax errors
7

SYNOPSIS

9         use Pod::Checker;
10
11         $syntax_okay = podchecker($filepath, $outputpath, %options);
12
13         my $checker = new Pod::Checker %options;
14         $checker->parse_from_file($filepath, \*STDERR);
15

OPTIONS/ARGUMENTS

17       $filepath is the input POD to read and $outputpath is where to write
18       POD syntax error messages. Either argument may be a scalar indicating a
19       file-path, or else a reference to an open filehandle.  If unspecified,
20       the input-file it defaults to "\*STDIN", and the output-file defaults
21       to "\*STDERR".
22
23   podchecker()
24       This function can take a hash of options:
25
26       -warnings => val
27           Turn warnings on/off. val is usually 1 for on, but higher values
28           trigger additional warnings. See "Warnings".
29

DESCRIPTION

31       podchecker will perform syntax checking of Perl5 POD format
32       documentation.
33
34       Curious/ambitious users are welcome to propose additional features they
35       wish to see in Pod::Checker and podchecker and verify that the checks
36       are consistent with perlpod.
37
38       The following checks are currently performed:
39
40       ·   Unknown '=xxxx' commands, unknown 'X<...>' interior-sequences, and
41           unterminated interior sequences.
42
43       ·   Check for proper balancing of "=begin" and "=end". The contents of
44           such a block are generally ignored, i.e. no syntax checks are
45           performed.
46
47       ·   Check for proper nesting and balancing of "=over", "=item" and
48           "=back".
49
50       ·   Check for same nested interior-sequences (e.g.  "L<...L<...>...>").
51
52       ·   Check for malformed or non-existing entities "E<...>".
53
54       ·   Check for correct syntax of hyperlinks "L<...>". See perlpod for
55           details.
56
57       ·   Check for unresolved document-internal links. This check may also
58           reveal misspelled links that seem to be internal links but should
59           be links to something else.
60

DIAGNOSTICS

62   Errors
63       ·   empty =headn
64
65           A heading ("=head1" or "=head2") without any text? That ain't no
66           heading!
67
68       ·   =over on line N without closing =back
69
70           The "=over" command does not have a corresponding "=back" before
71           the next heading ("=head1" or "=head2") or the end of the file.
72
73       ·   =item without previous =over
74
75       ·   =back without previous =over
76
77           An "=item" or "=back" command has been found outside a
78           "=over"/"=back" block.
79
80       ·   No argument for =begin
81
82           A "=begin" command was found that is not followed by the formatter
83           specification.
84
85       ·   =end without =begin
86
87           A standalone "=end" command was found.
88
89       ·   Nested =begin's
90
91           There were at least two consecutive "=begin" commands without the
92           corresponding "=end". Only one "=begin" may be active at a time.
93
94       ·   =for without formatter specification
95
96           There is no specification of the formatter after the "=for"
97           command.
98
99       ·   unresolved internal link NAME
100
101           The given link to NAME does not have a matching node in the current
102           POD. This also happened when a single word node name is not
103           enclosed in "".
104
105       ·   Unknown command "CMD"
106
107           An invalid POD command has been found. Valid are "=head1",
108           "=head2", "=head3", "=head4", "=over", "=item", "=back", "=begin",
109           "=end", "=for", "=pod", "=cut"
110
111       ·   Unknown interior-sequence "SEQ"
112
113           An invalid markup command has been encountered. Valid are: "B<>",
114           "C<>", "E<>", "F<>", "I<>", "L<>", "S<>", "X<>", "Z<>"
115
116       ·   nested commands CMD<...CMD<...>...>
117
118           Two nested identical markup commands have been found. Generally
119           this does not make sense.
120
121       ·   garbled entity STRING
122
123           The STRING found cannot be interpreted as a character entity.
124
125       ·   Entity number out of range
126
127           An entity specified by number (dec, hex, oct) is out of range
128           (1-255).
129
130       ·   malformed link L<>
131
132           The link found cannot be parsed because it does not conform to the
133           syntax described in perlpod.
134
135       ·   nonempty Z<>
136
137           The "Z<>" sequence is supposed to be empty.
138
139       ·   empty X<>
140
141           The index entry specified contains nothing but whitespace.
142
143       ·   Spurious text after =pod / =cut
144
145           The commands "=pod" and "=cut" do not take any arguments.
146
147       ·   Spurious character(s) after =back
148
149           The "=back" command does not take any arguments.
150
151   Warnings
152       These may not necessarily cause trouble, but indicate mediocre style.
153
154       ·   multiple occurrence of link target name
155
156           The POD file has some "=item" and/or "=head" commands that have the
157           same text. Potential hyperlinks to such a text cannot be unique
158           then.  This warning is printed only with warning level greater than
159           one.
160
161       ·   line containing nothing but whitespace in paragraph
162
163           There is some whitespace on a seemingly empty line. POD is very
164           sensitive to such things, so this is flagged. vi users switch on
165           the list option to avoid this problem.
166
167       ·   previous =item has no contents
168
169           There is a list "=item" right above the flagged line that has no
170           text contents. You probably want to delete empty items.
171
172       ·   preceding non-item paragraph(s)
173
174           A list introduced by "=over" starts with a text or verbatim
175           paragraph, but continues with "=item"s. Move the non-item paragraph
176           out of the "=over"/"=back" block.
177
178       ·   =item type mismatch (one vs. two)
179
180           A list started with e.g. a bullet-like "=item" and continued with a
181           numbered one. This is obviously inconsistent. For most translators
182           the type of the first "=item" determines the type of the list.
183
184       ·   N unescaped "<>" in paragraph
185
186           Angle brackets not written as "<lt>" and "<gt>" can potentially
187           cause errors as they could be misinterpreted as markup commands.
188           This is only printed when the -warnings level is greater than 1.
189
190       ·   Unknown entity
191
192           A character entity was found that does not belong to the standard
193           ISO set or the POD specials "verbar" and "sol".
194
195       ·   No items in =over
196
197           The list opened with "=over" does not contain any items.
198
199       ·   No argument for =item
200
201           "=item" without any parameters is deprecated. It should either be
202           followed by "*" to indicate an unordered list, by a number
203           (optionally followed by a dot) to indicate an ordered (numbered)
204           list or simple text for a definition list.
205
206       ·   empty section in previous paragraph
207
208           The previous section (introduced by a "=head" command) does not
209           contain any text. This usually indicates that something is missing.
210           Note: A "=head1" followed immediately by "=head2" does not trigger
211           this warning.
212
213       ·   Verbatim paragraph in NAME section
214
215           The NAME section ("=head1 NAME") should consist of a single
216           paragraph with the script/module name, followed by a dash `-' and a
217           very short description of what the thing is good for.
218
219       ·   =headn without preceding higher level
220
221           For example if there is a "=head2" in the POD file prior to a
222           "=head1".
223
224   Hyperlinks
225       There are some warnings with respect to malformed hyperlinks:
226
227       ·   ignoring leading/trailing whitespace in link
228
229           There is whitespace at the beginning or the end of the contents of
230           L<...>.
231
232       ·   (section) in '$page' deprecated
233
234           There is a section detected in the page name of L<...>, e.g.
235           "L<passwd(2)>". POD hyperlinks may point to POD documents only.
236           Please write "C<passwd(2)>" instead. Some formatters are able to
237           expand this to appropriate code. For links to (builtin) functions,
238           please say "L<perlfunc/mkdir>", without ().
239
240       ·   alternative text/node '%s' contains non-escaped | or /
241
242           The characters "|" and "/" are special in the L<...> context.
243           Although the hyperlink parser does its best to determine which "/"
244           is text and which is a delimiter in case of doubt, one ought to
245           escape these literal characters like this:
246
247             /     E<sol>
248             |     E<verbar>
249

RETURN VALUE

251       podchecker returns the number of POD syntax errors found or -1 if there
252       were no POD commands at all found in the file.
253

EXAMPLES

255       See "SYNOPSIS"
256

INTERFACE

258       While checking, this module collects document properties, e.g. the
259       nodes for hyperlinks ("=headX", "=item") and index entries ("X<>").
260       POD translators can use this feature to syntax-check and get the nodes
261       in a first pass before actually starting to convert. This is expensive
262       in terms of execution time, but allows for very robust conversions.
263
264       Since PodParser-1.24 the Pod::Checker module uses only the poderror
265       method to print errors and warnings. The summary output (e.g.  "Pod
266       syntax OK") has been dropped from the module and has been included in
267       podchecker (the script). This allows users of Pod::Checker to control
268       completely the output behavior. Users of podchecker (the script) get
269       the well-known behavior.
270
271       "Pod::Checker->new( %options )"
272           Return a reference to a new Pod::Checker object that inherits from
273           Pod::Parser and is used for calling the required methods later. The
274           following options are recognized:
275
276           "-warnings => num"
277             Print warnings if "num" is true. The higher the value of "num",
278           the more warnings are printed. Currently there are only levels 1
279           and 2.
280
281           "-quiet => num"
282             If "num" is true, do not print any errors/warnings. This is
283           useful when Pod::Checker is used to munge POD code into plain text
284           from within POD formatters.
285
286       "$checker->poderror( @args )"
287       "$checker->poderror( {%opts}, @args )"
288           Internal method for printing errors and warnings. If no options are
289           given, simply prints "@_". The following options are recognized and
290           used to form the output:
291
292             -msg
293
294           A message to print prior to @args.
295
296             -line
297
298           The line number the error occurred in.
299
300             -file
301
302           The file (name) the error occurred in.
303
304             -severity
305
306           The error level, should be 'WARNING' or 'ERROR'.
307
308       "$checker->num_errors()"
309           Set (if argument specified) and retrieve the number of errors
310           found.
311
312       "$checker->num_warnings()"
313           Set (if argument specified) and retrieve the number of warnings
314           found.
315
316       "$checker->name()"
317           Set (if argument specified) and retrieve the canonical name of POD
318           as found in the "=head1 NAME" section.
319
320       "$checker->node()"
321           Add (if argument specified) and retrieve the nodes (as defined by
322           "=headX" and "=item") of the current POD. The nodes are returned in
323           the order of their occurrence. They consist of plain text, each
324           piece of whitespace is collapsed to a single blank.
325
326       "$checker->idx()"
327           Add (if argument specified) and retrieve the index entries (as
328           defined by "X<>") of the current POD. They consist of plain text,
329           each piece of whitespace is collapsed to a single blank.
330
331       "$checker->hyperlink()"
332           Add (if argument specified) and retrieve the hyperlinks (as defined
333           by "L<>") of the current POD. They consist of a 2-item array: line
334           number and "Pod::Hyperlink" object.
335

AUTHOR

337       Please report bugs using <http://rt.cpan.org>.
338
339       Brad Appleton <bradapp@enteract.com> (initial version), Marek Rouchal
340       <marekr@cpan.org>
341
342       Based on code for Pod::Text::pod2text() written by Tom Christiansen
343       <tchrist@mox.perl.com>
344
345
346
347perl v5.12.4                      2011-06-01                 Pod::Checker(3pm)
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