1 # Pod::ParseLink -- Parse an L<> formatting code in POD text.
3 # Copyright 2001, 2008 by Russ Allbery <rra@stanford.edu>
5 # This program is free software; you may redistribute it and/or modify it
6 # under the same terms as Perl itself.
8 # This module implements parsing of the text of an L<> formatting code as
9 # defined in perlpodspec. It should be suitable for any POD formatter. It
10 # exports only one function, parselink(), which returns the five-item parse
11 # defined in perlpodspec.
13 # Perl core hackers, please note that this module is also separately
14 # maintained outside of the Perl core as part of the podlators. Please send
15 # me any patches at the address above in addition to sending them to the
16 # standard Perl mailing lists.
18 ##############################################################################
19 # Modules and declarations
20 ##############################################################################
22 package Pod::ParseLink;
27 use vars qw(@EXPORT @ISA $VERSION);
31 @EXPORT = qw(parselink);
35 ##############################################################################
37 ##############################################################################
39 # Parse the name and section portion of a link into a name and section.
45 # If the whole link is enclosed in quotes, interpret it all as a section
46 # even if it contains a slash.
47 return (undef, $1) if ($link =~ /^"\s*(.*?)\s*"$/);
49 # Split into page and section on slash, and then clean up quoting in the
50 # section. If there is no section and the name contains spaces, also
51 # guess that it's an old section link.
52 my ($page, $section) = split (/\s*\/\s*/, $link, 2);
53 $section =~ s/^"\s*(.*?)\s*"$/$1/ if $section;
54 if ($page && $page =~ / / && !defined ($section)) {
58 $page = undef unless $page;
59 $section = undef unless $section;
61 return ($page, $section);
64 # Infer link text from the page and section.
66 my ($page, $section) = @_;
68 if ($page && !$section) {
70 } elsif (!$page && $section) {
71 $inferred = '"' . $section . '"';
72 } elsif ($page && $section) {
73 $inferred = '"' . $section . '" in ' . $page;
78 # Given the contents of an L<> formatting code, parse it into the link text,
79 # the possibly inferred link text, the name or URL, the section, and the type
80 # of link (pod, man, or url).
84 if ($link =~ /\A\w+:[^:\s]\S*\Z/) {
85 return (undef, $link, $link, undef, 'url');
89 ($text, $link) = split (/\|/, $link, 2);
91 my ($name, $section) = _parse_section ($link);
92 my $inferred = $text || _infer_text ($name, $section);
93 my $type = ($name && $name =~ /\(\S*\)/) ? 'man' : 'pod';
94 return ($text, $inferred, $name, $section, $type);
98 ##############################################################################
99 # Module return value and documentation
100 ##############################################################################
102 # Ensure we evaluate to true.
108 Pod::ParseLink - Parse an LE<lt>E<gt> formatting code in POD text
116 my ($text, $inferred, $name, $section, $type) = parselink ($link);
120 This module only provides a single function, parselink(), which takes the
121 text of an LE<lt>E<gt> formatting code and parses it. It returns the
122 anchor text for the link (if any was given), the anchor text possibly
123 inferred from the name and section, the name or URL, the section if any,
124 and the type of link. The type will be one of C<url>, C<pod>, or C<man>,
125 indicating a URL, a link to a POD page, or a link to a Unix manual page.
127 Parsing is implemented per L<perlpodspec>. For backward compatibility,
128 links where there is no section and name contains spaces, or links where the
129 entirety of the link (except for the anchor text if given) is enclosed in
130 double-quotes are interpreted as links to a section (LE<lt>/sectionE<gt>).
132 The inferred anchor text is implemented per L<perlpodspec>:
134 L<name> => L<name|name>
135 L</section> => L<"section"|/section>
136 L<name/section> => L<"section" in name|name/section>
138 The name may contain embedded EE<lt>E<gt> and ZE<lt>E<gt> formatting codes,
139 and the section, anchor text, and inferred anchor text may contain any
140 formatting codes. Any double quotes around the section are removed as part
141 of the parsing, as is any leading or trailing whitespace.
143 If the text of the LE<lt>E<gt> escape is entirely enclosed in double
144 quotes, it's interpreted as a link to a section for backward
147 No attempt is made to resolve formatting codes. This must be done after
148 calling parselink() (since EE<lt>E<gt> formatting codes can be used to
149 escape characters that would otherwise be significant to the parser and
150 resolving them before parsing would result in an incorrect parse of a
151 formatting code like:
153 L<verticalE<verbar>barE<sol>slash>
155 which should be interpreted as a link to the C<vertical|bar/slash> POD page
156 and not as a link to the C<slash> section of the C<bar> POD page with an
157 anchor text of C<vertical>. Note that not only the anchor text will need to
158 have formatting codes expanded, but so will the target of the link (to deal
159 with EE<lt>E<gt> and ZE<lt>E<gt> formatting codes), and special handling of
160 the section may be necessary depending on whether the translator wants to
161 consider markup in sections to be significant when resolving links. See
162 L<perlpodspec> for more information.
168 The current version of this module is always available from its web site at
169 L<http://www.eyrie.org/~eagle/software/podlators/>.
173 Russ Allbery <rra@stanford.edu>.
175 =head1 COPYRIGHT AND LICENSE
177 Copyright 2001, 2008 Russ Allbery <rra@stanford.edu>.
179 This program is free software; you may redistribute it and/or modify it
180 under the same terms as Perl itself.