1Data::Section(3) User Contributed Perl Documentation Data::Section(3)
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6 Data::Section - read multiple hunks of data out of your DATA section
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9 version 0.200008
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12 package Letter::Resignation;
13 use Data::Section -setup;
14
15 sub quit {
16 my ($class, $angry, %arg) = @_;
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18 my $template = $class->section_data(
19 ($angry ? "angry_" : "professional_") . "letter"
20 );
21
22 return fill_in($$template, \%arg);
23 }
24
25 __DATA__
26 __[ angry_letter ]__
27 Dear jerks,
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29 I quit!
30
31 --
32 {{ $name }}
33 __[ professional_letter ]__
34 Dear {{ $boss }},
35
36 I quit, jerks!
37
38
39 --
40 {{ $name }}
41
43 Data::Section provides an easy way to access multiple named chunks of
44 line-oriented data in your module's DATA section. It was written to
45 allow modules to store their own templates, but probably has other
46 uses.
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49 This library should run on perls released even a long time ago. It
50 should work on any version of perl released in the last five years.
51
52 Although it may work on older versions of perl, no guarantee is made
53 that the minimum required version will not be increased. The version
54 may be increased for any reason, and there is no promise that patches
55 will be accepted to lower the minimum required perl.
56
58 You will need to use "__DATA__" sections and not "__END__" sections.
59 Yes, it matters. Who knew!
60
62 To get the methods exported by Data::Section, you must import like
63 this:
64
65 use Data::Section -setup;
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67 Optional arguments may be given to Data::Section like this:
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69 use Data::Section -setup => { ... };
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71 Valid arguments are:
72
73 encoding - if given, gives the encoding needed to decode bytes in
74 data sections; default; UTF-8
75
76 the special value "bytes" will leave the bytes in the string
77 verbatim
78
79 inherit - if true, allow packages to inherit the data of the packages
80 from which they inherit; default: true
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82 header_re - if given, changes the regex used to find section headers
83 in the data section; it should leave the section name in $1
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85 default_name - if given, allows the first section to has no header and set
86 its name
87
88 Three methods are exported by Data::Section:
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90 section_data
91 my $string_ref = $pkg->section_data($name);
92
93 This method returns a reference to a string containing the data from
94 the name section, either in the invocant's "DATA" section or in that of
95 one of its ancestors. (The ancestor must also derive from the class
96 that imported Data::Section.)
97
98 By default, named sections are delimited by lines that look like this:
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100 __[ name ]__
101
102 You can use as many underscores as you want, and the space around the
103 name is optional. This pattern can be configured with the "header_re"
104 option (see above). If present, a single leading "\" is removed, so
105 that sections can encode lines that look like section delimiters.
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107 When a line containing only "__END__" is reached, all processing of
108 sections ends.
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110 section_data_names
111 my @names = $pkg->section_data_names;
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113 This returns a list of all the names that will be recognized by the
114 "section_data" method.
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116 merged_section_data
117 my $data = $pkg->merged_section_data;
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119 This method returns a hashref containing all the data extracted from
120 the package data for all the classes from which the invocant inherits
121 -- as long as those classes also inherit from the package into which
122 Data::Section was imported.
123
124 In other words, given this inheritance tree:
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126 A
127 \
128 B C
129 \ /
130 D
131
132 ...if Data::Section was imported by A, then when D's
133 "merged_section_data" is invoked, C's data section will not be
134 considered. (This prevents the read position of C's data handle from
135 being altered unexpectedly.)
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137 The keys in the returned hashref are the section names, and the values
138 are references to the strings extracted from the data sections.
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140 merged_section_data_names
141 my @names = $pkg->merged_section_data_names;
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143 This returns a list of all the names that will be recognized by the
144 "merged_section_data" method.
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146 local_section_data
147 my $data = $pkg->local_section_data;
148
149 This method returns a hashref containing all the data extracted from
150 the package on which the method was invoked. If called on an object,
151 it will operate on the package into which the object was blessed.
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153 This method needs to be used carefully, because it's weird. It returns
154 only the data for the package on which it was invoked. If the package
155 on which it was invoked has no data sections, it returns an empty
156 hashref.
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158 local_section_data_names
159 my @names = $pkg->local_section_data_names;
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161 This returns a list of all the names that will be recognized by the
162 "local_section_data" method.
163
165 MooseX::Declare and namespace::autoclean
166 The namespace::autoclean library automatically cleans foreign routines
167 from a class, including those imported by Data::Section.
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169 MooseX::Declare does the same thing, and can also cause your "__DATA__"
170 section to appear outside your class's package.
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172 These are easy to address. The Sub::Exporter::ForMethods library
173 provides an installer that will cause installed methods to appear to
174 come from the class and avoid autocleaning. Using an explicit
175 "package" statement will keep the data section in the correct package.
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177 package Foo;
178
179 use MooseX::Declare;
180 class Foo {
181
182 # Utility to tell Sub::Exporter modules to export methods.
183 use Sub::Exporter::ForMethods qw( method_installer );
184
185 # method_installer returns a sub.
186 use Data::Section { installer => method_installer }, -setup;
187
188 method my_method {
189 my $content_ref = $self->section_data('SectionA');
190
191 print $$content_ref;
192 }
193 }
194
195 __DATA__
196 __[ SectionA ]__
197 Hello, world.
198
200 • article for RJBS Advent 2009
201 <http://advent.rjbs.manxome.org/2009/2009-12-09.html>
202
203 • Inline::Files does something that is at first look similar,
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205 but it works with source filters, and contains the warning:
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207 It is possible that this module may overwrite the source code in files that
208 use it. To protect yourself against this possibility, you are strongly
209 advised to use the -backup option described in "Safety first".
210
211 Enough said.
212
214 Ricardo SIGNES <cpan@semiotic.systems>
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217 • Christian Walde <walde.christian@googlemail.com>
218
219 • Dan Kogai <dankogai+github@gmail.com>
220
221 • David Golden <dagolden@cpan.org>
222
223 • David Steinbrunner <dsteinbrunner@pobox.com>
224
225 • Graham Ollis <plicease@cpan.org>
226
227 • Karen Etheridge <ether@cpan.org>
228
229 • Kenichi Ishigaki <ishigaki@cpan.org>
230
231 • kentfredric <kentfredric+gravitar@gmail.com>
232
233 • Ricardo Signes <rjbs@semiotic.systems>
234
235 • Tatsuhiko Miyagawa <miyagawa@bulknews.net>
236
238 This software is copyright (c) 2008 by Ricardo SIGNES.
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240 This is free software; you can redistribute it and/or modify it under
241 the same terms as the Perl 5 programming language system itself.
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245perl v5.36.0 2023-01-20 Data::Section(3)