1Exporter::Easy(3)     User Contributed Perl Documentation    Exporter::Easy(3)
2
3
4

NAME

6       Exporter::Easy - Takes the drudgery out of Exporting symbols
7

SYNOPSIS

9       In module YourModule.pm:
10
11         package YourModule;
12         use Exporter::Easy (
13           OK => [ '$munge', 'frobnicate' ] # symbols to export on request
14         );
15
16       In other files which wish to use YourModule:
17
18         use ModuleName qw(frobnicate);      # import listed symbols
19         frobnicate ($left, $right)          # calls YourModule::frobnicate
20

DESCRIPTION

22       Exporter::Easy makes using Exporter easy.  In its simplest case, it
23       allows you to drop the boilerplate code that comes with using Exporter,
24       so
25
26         require Exporter;
27         use base qw( Exporter );
28         use vars qw( @EXPORT );
29         @EXPORT = ( 'init' );
30
31       becomes
32
33         use Exporter::Easy ( EXPORT => [ 'init' ] );
34
35       and more complicated situations where you use tags to build lists and
36       more tags become easy, like this
37
38         use Exporter::Easy (
39               EXPORT => [qw( init :base )],
40               TAGS => [
41                       base => [qw( open close )],
42                       read => [qw( read sysread readline )],
43                       write => [qw( print write writeline )],
44                       misc => [qw( select flush )],
45                       all => [qw( :base :read :write :misc)],
46                       no_misc => [qw( :all !:misc )],
47               ],
48               OK => [qw( some other stuff )],
49         );
50
51       This will set @EXPORT, @EXPORT_OK, @EXPORT_FAIL and %EXPORT_TAGS in the
52       current package, add Exporter to that package's @ISA and do a "use
53       vars" on all the variables mentioned. The rest is handled as normal by
54       Exporter.
55

HOW TO USE IT

57       Put
58
59               use Exporter::Easy ( KEY => value, ...);
60
61       in your package. Arguments are passes as key-value pairs, the following
62       keys are available
63
64       TAGS
65           The value should be a reference to a list that goes like (TAG_NAME,
66           TAG_VALUE, TAG_NAME, TAG_VALUE, ...), where TAG_NAME is a string
67           and TAG_VALUE is a reference to an array of symbols and tags. For
68           example
69
70             TAGS => [
71               file => [ 'open', 'close', 'read', 'write'],
72               string => [ 'length', 'substr', 'chomp' ],
73               hash => [ 'keys', 'values', 'each' ],
74               all => [ ':file', ':string', ':hash' ],
75               some => [':all', '!open', ':hash'],
76             ]
77
78           This is used to fill the %EXPORT_TAGS in your package. You can
79           build tags from other tags - in the example above the tag "all"
80           will contain all the symbols from "file", "string" and "hash". You
81           can also subtract symbols and tags - in the example above, "some"
82           contains the symbols from all but with "open" removed and all the
83           symbols from "hash" removed.
84
85           The rule is that any symbol starting with a ':' is taken to be a
86           tag which has been defined previously (if it's not defined you'll
87           get an error). If a symbol is preceded by a '!' it will be
88           subtracted from the list, otherwise it is added.
89
90           If you try to redefine a tag you will also get an error.
91
92           All the symbols which occur while building the tags are
93           automatically added your package's @EXPORT_OK array.
94
95       OK  The value should be a reference to a list of symbols and tags
96           (which will be exapanded). These symbols will be added to the
97           @EXPORT_OK array in your package. Using OK and and OK_ONLY together
98           will give an error.
99
100       OK_ONLY
101           The value should be a reference to a list of symbols and tags
102           (which will be exapanded). The @EXPORT_OK array in your package
103           will contains only these symbols.. This totally overrides the
104           automatic population of this array. If you just want to add some
105           symbols to the list that Exporter::Easy has automatically built
106           then you should use OK instead. Using OK_ONLY and OK together will
107           give an error.
108
109       EXPORT
110           The value should be a reference to a list of symbol names and tags.
111           Any tags will be expanded and the resulting list of symbol names
112           will be placed in the @EXPORT array in your package. The tag
113           created by the ALL key is not available at this stage.
114
115       FAIL
116           The value should be a reference to a list of symbol names and tags.
117           The tags will be expanded and the resulting list of symbol names
118           will be placed in the @EXPORT_FAIL array in your package. They will
119           also be added to the @EXPORT_OK list.
120
121       ALL The value should be the name of tag that doesn't yet exist. This
122           tag will contain a list of all symbols which can be exported.
123
124       ISA If you set this to 0 then Exporter will not be added to your @ISA
125           list.
126
127       VARS
128           If this is set to 1 or not provided then all $, @ and % variables
129           mentioned previously will be available to use in your package as if
130           you had done a "use vars" on them. If it's set to a reference to a
131           list of symbols and tags then only those symbols will be available.
132           If it's set to 0 then you'll have to do your own "use vars" in your
133           package.
134

PROCESSING ORDER

136       We need take the information provided and build @EXPORT, @EXPORT_OK,
137       @EXPORT_FAIL and %EXPORT_TAGS in the calling package. We may also need
138       to build a tag with all of the symbols and to make all the variables
139       useable under strict.
140
141       The arguments are processed in the following order: TAGS, EXPORT, OK,
142       OK_ONLY and FAIL, ALL, VARS and finally ISA. This means you cannot use
143       the tag created by ALL anywhere except in VARS (although vars defaults
144       to using all symbols anyway).
145

SEE ALSO

147       Exporter is the grandaddy of all Exporter modules, and bundled with
148       Perl itself, unlike the rest of the modules listed here. Look at the
149       documentation for this module to see more explanation of the OK, EXPORT
150       and other variables.
151
152       Attribute::Exporter defines attributes which you use to mark which subs
153       and variables you want to export, and how.
154
155       Exporter::Simple also uses attributes to control the export of
156       functions and variables from your module.
157
158       Const::Exporter makes it easy to create a module that exports
159       constants.
160
161       Constant::Exporter is another module that makes it easy to create
162       modules that define and export constants.
163
164       Sub::Exporter is a "sophisticated exporter for custom-built routines";
165       it lets you provide generators that can be used to customise what gets
166       imported when someone uses your module.
167
168       Exporter::Tiny provides the same features as Sub::Exporter, but relying
169       only on core dependencies.
170
171       Exporter::Shiny is a shortcut for Exporter::Tiny that provides a more
172       concise notation for providing optional exports.
173
174       Exporter::Declare provides syntactic sugar to make the export status of
175       your functions part of their declaration. Kind of.
176
177       AppConfig::Exporter lets you export part of an AppConfig-based
178       configuration.
179
180       Exporter::Lexical lets you export lexical subs from your module.
181
182       Constant::Exporter::Lazy lets you write a module that exports function-
183       style constants, which are instantiated lazily.
184
185       Exporter::Auto will export everything from your module that it thinks
186       is a public function (name doesn't start with an underscore).
187
188       Class::Exporter lets you export class methods as regular subroutines.
189
190       Xporter is like Exporter, but with persistent defaults and auto-ISA.
191

REPOSITORY

193       <https://github.com/neilb/Exporter-Easy>
194

AUTHOR

196       Written by Fergal Daly <fergal@esatclear.ie>.
197

LICENSE

199       Under the same license as Perl itself
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203perl v5.34.0                      2022-01-21                 Exporter::Easy(3)
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