1Tidy(3) User Contributed Perl Documentation Tidy(3)
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6 Exporter::Tidy - Another way of exporting symbols
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9 package MyModule::HTTP;
10 use Exporter::Tidy
11 default => [ qw(get) ],
12 other => [ qw(post head) ];
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14 use MyModule::HTTP qw(:all);
15 use MyModule::HTTP qw(:default post);
16 use MyModule::HTTP qw(post);
17 use MyModule::HTTP _prefix => 'http_', qw(get post);
18 use MyModule::HTTP qw(get post), _prefix => 'http_', qw(head);
19 use MyModule::HTTP
20 _prefix => 'foo', qw(get post),
21 _prefix => 'bar', qw(get head);
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23 package MyModule::Foo;
24 use Exporter::Tidy
25 default => [ qw($foo $bar quux) ],
26 _map => {
27 '$foo' => \$my_foo,
28 '$bar' => \$my_bar,
29 quux => sub { print "Hello, world!\n" }
30 };
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32 package MyModule::Constants;
33 use Exporter::Tidy
34 default => [ qw(:all) ],
35 _map => {
36 FOO => sub () { 1 },
37 BAR => sub () { 2 },
38 OK => sub () { 1 },
39 FAILURE => sub () { 0 }
40 };
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43 This module serves as an easy, clean alternative to Exporter. Unlike
44 Exporter, it is not subclassed, but it simply exports a custom import()
45 into your namespace.
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47 With Exporter::Tidy, you don't need to use any package global in your
48 module. Even the subs you export can be lexically scoped.
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50 use Exporter::Tidy LIST
51 The list supplied to "use Exporter::Tidy" should be a key-value list.
52 Each key serves as a tag, used to group exportable symbols. The values
53 in this key-value list should be array references. There are a few
54 special tags:
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56 all If you don't provide an "all" tag yourself, Tidy::Exporter
57 will generate one for you. It will contain all exportable
58 symbols.
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60 default The "default" tag will be used if the user supplies no list
61 to the "use" statement.
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63 _map With _map you should not use an array reference, but a hash
64 reference. Here, you can rewrite symbols to other names or
65 even define one on the spot by using a reference. You can
66 "foo => 'bar'" to export "bar" if "foo" is requested.
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68 Exportable symbols
69 Every symbol specified in a tag's array, or used as a key in _map's
70 hash is exportable.
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72 Symbol types
73 You can export subs, scalars, arrays, hashes and typeglobs. Do not use
74 an ampersand ("&") for subs. All other types must have the proper
75 sigil.
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77 Importing from a module that uses Exporter::Tidy
78 You can use either a symbol name (without the sigil if it is a sub, or
79 with the appropriate sigil if it is not), or a tag name prefixed with a
80 colon. It is possible to import a symbol twice, but a symbol is never
81 exported twice under the same name, so you can use tags that overlap.
82 If you supply any list to the "use" statement, ":default" is no longer
83 used if not specified explicitly.
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85 To avoid name clashes, it is possible to have symbols prefixed. Supply
86 "_prefix" followed by the prefix that you want. Multiple can be used.
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88 use Some::Module qw(foo bar), _prefix => 'some_', qw(quux);
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90 imports Some::Module::foo as foo, Some::Module::bar as bar, and
91 Some::Module::quux as some_quux. See the SYNOPSIS for more examples.
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94 Exporter::Tidy "versus" Exporter
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96 These numbers are valid for my Linux system with Perl 5.8.0. Your
97 mileage may vary.
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99 Speed
100 Exporting two symbols using no import list (@EXPORT and :default) is
101 approximately 10% faster with Exporter. But if you use any tag
102 explicitly, Exporter::Tidy is more than twice as fast (!) as Exporter.
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104 Memory usage
105 perl -le'require X; print((split " ", `cat /proc/$$/stat`)[22])'
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107 No module 3022848
108 Exporter::Tidy 3067904
109 Exporter 3084288
110 Exporter::Heavy 3174400
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112 Exporter loads Exporter::Heavy automatically when needed. It is needed
113 to support exporter tags, amongst other things. Exporter::Tidy has all
114 functionality built into one module.
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116 Both Exporter(::Heavy) and Exporter::Tidy delay loading Carp until it
117 is needed.
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119 Usage
120 Exporter is subclassed and gets its information from package global
121 variables like @EXPORT, @EXPORT_OK and %EXPORT_TAGS.
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123 Exporter::Tidy exports an "import" method and gets its information from
124 the "use" statement.
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127 Pick your favourite OSI approved license :)
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129 http://www.opensource.org/licenses/alphabetical
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132 Thanks to Aristotle Pagaltzis for suggesting the name Exporter::Tidy.
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135 Juerd Waalboer <juerd@cpan.org> <http://juerd.nl/>
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139perl v5.32.0 2020-07-28 Tidy(3)