1App::Cmd(3) User Contributed Perl Documentation App::Cmd(3)
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6 App::Cmd - write command line apps with less suffering
7
9 version 0.334
10
12 in yourcmd:
13
14 use YourApp;
15 YourApp->run;
16
17 in YourApp.pm:
18
19 package YourApp;
20 use App::Cmd::Setup -app;
21 1;
22
23 in YourApp/Command/blort.pm:
24
25 package YourApp::Command::blort;
26 use YourApp -command;
27 use strict; use warnings;
28
29 sub abstract { "blortex algorithm" }
30
31 sub description { "Long description on blortex algorithm" }
32
33 sub opt_spec {
34 return (
35 [ "blortex|X", "use the blortex algorithm" ],
36 [ "recheck|r", "recheck all results" ],
37 );
38 }
39
40 sub validate_args {
41 my ($self, $opt, $args) = @_;
42
43 # no args allowed but options!
44 $self->usage_error("No args allowed") if @$args;
45 }
46
47 sub execute {
48 my ($self, $opt, $args) = @_;
49
50 my $result = $opt->{blortex} ? blortex() : blort();
51
52 recheck($result) if $opt->{recheck};
53
54 print $result;
55 }
56
57 and, finally, at the command line:
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59 knight!rjbs$ yourcmd blort --recheck
60
61 All blorts successful.
62
64 App::Cmd is intended to make it easy to write complex command-line
65 applications without having to think about most of the annoying things
66 usually involved.
67
68 For information on how to start using App::Cmd, see App::Cmd::Tutorial.
69
71 This module has a long-term perl support period. That means it will
72 not require a version of perl released fewer than five years ago.
73
74 Although it may work on older versions of perl, no guarantee is made
75 that the minimum required version will not be increased. The version
76 may be increased for any reason, and there is no promise that patches
77 will be accepted to lower the minimum required perl.
78
80 new
81 my $cmd = App::Cmd->new(\%arg);
82
83 This method returns a new App::Cmd object. During initialization,
84 command plugins will be loaded.
85
86 Valid arguments are:
87
88 no_commands_plugin - if true, the command list plugin is not added
89
90 no_help_plugin - if true, the help plugin is not added
91
92 no_version_plugin - if true, the version plugin is not added
93
94 show_version_cmd - if true, the version command will be shown in the
95 command list
96
97 plugin_search_path - The path to search for commands in. Defaults to
98 results of plugin_search_path method
99
100 If "no_commands_plugin" is not given, App::Cmd::Command::commands will
101 be required, and it will be registered to handle all of its command
102 names not handled by other plugins.
103
104 If "no_help_plugin" is not given, App::Cmd::Command::help will be
105 required, and it will be registered to handle all of its command names
106 not handled by other plugins. Note: "help" is the default command, so
107 if you do not load the default help plugin, you should provide your own
108 or override the "default_command" method.
109
110 If "no_version_plugin" is not given, App::Cmd::Command::version will be
111 required to show the application's version with command "--version". By
112 default, the version command is not included in the command list. Pass
113 "show_version_cmd" to include the version command in the list.
114
115 run
116 $cmd->run;
117
118 This method runs the application. If called the class, it will
119 instantiate a new App::Cmd object to run.
120
121 It determines the requested command (generally by consuming the first
122 command-line argument), finds the plugin to handle that command, parses
123 the remaining arguments according to that plugin's rules, and runs the
124 plugin.
125
126 It passes the contents of the global argument array (@ARGV) to
127 ""prepare_command"", but @ARGV is not altered by running an App::Cmd.
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129 prepare_args
130 Normally App::Cmd uses @ARGV for its commandline arguments. You can
131 override this method to change that behavior for testing or otherwise.
132
133 default_args
134 If "prepare_args" is not changed and there are no arguments in @ARGV,
135 this method is called and should return an arrayref to be used as the
136 arguments to the program. By default, it returns an empty arrayref.
137
138 abstract
139 sub abstract { "command description" }
140
141 Defines the command abstract: a short description that will be printed
142 in the main command options list.
143
144 description
145 sub description { "Long description" }
146
147 Defines a longer command description that will be shown when the user
148 asks for help on a specific command.
149
150 arg0
151 full_arg0
152 my $program_name = $app->arg0;
153
154 my $full_program_name = $app->full_arg0;
155
156 These methods return the name of the program invoked to run this
157 application. This is determined by inspecting $0 when the App::Cmd
158 object is instantiated, so it's probably correct, but doing weird
159 things with App::Cmd could lead to weird values from these methods.
160
161 If the program was run like this:
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163 knight!rjbs$ ~/bin/rpg dice 3d6
164
165 Then the methods return:
166
167 arg0 - rpg
168 full_arg0 - /Users/rjbs/bin/rpg
169
170 These values are captured when the App::Cmd object is created, so it is
171 safe to assign to $0 later.
172
173 prepare_command
174 my ($cmd, $opt, @args) = $app->prepare_command(@ARGV);
175
176 This method will load the plugin for the requested command, use its
177 options to parse the command line arguments, and eventually return
178 everything necessary to actually execute the command.
179
180 default_command
181 This method returns the name of the command to run if none is given on
182 the command line. The default default is "help"
183
184 execute_command
185 $app->execute_command($cmd, \%opt, @args);
186
187 This method will invoke "validate_args" and then "run" on $cmd.
188
189 plugin_search_path
190 This method returns the plugin_search_path as set. The default
191 implementation, if called on "YourApp::Cmd" will return
192 "YourApp::Cmd::Command"
193
194 This is a method because it's fun to override it with, for example:
195
196 use constant plugin_search_path => __PACKAGE__;
197
198 allow_any_unambiguous_abbrev
199 If this method returns true (which, by default, it does not), then any
200 unambiguous abbreviation for a registered command name will be allowed
201 as a means to use that command. For example, given the following
202 commands:
203
204 reticulate
205 reload
206 rasterize
207
208 Then the user could use "ret" for "reticulate" or "ra" for "rasterize"
209 and so on.
210
211 global_options
212 if ($cmd->app->global_options->{verbose}) { ... }
213
214 This method returns the running application's global options as a
215 hashref. If there are no options specified, an empty hashref is
216 returned.
217
218 set_global_options
219 $app->set_global_options(\%opt);
220
221 This method sets the global options.
222
223 command_names
224 my @names = $cmd->command_names;
225
226 This returns the commands names which the App::Cmd object will handle.
227
228 command_groups
229 my @groups = $cmd->commands_groups;
230
231 This method can be implemented to return a grouped list of command
232 names with optional headers. Each group is given as arrayref and each
233 header as string. If an empty list is returned, the commands plugin
234 will show two groups without headers: the first group is for the "help"
235 and "commands" commands, and all other commands are in the second
236 group.
237
238 command_plugins
239 my @plugins = $cmd->command_plugins;
240
241 This method returns the package names of the plugins that implement the
242 App::Cmd object's commands.
243
244 plugin_for
245 my $plugin = $cmd->plugin_for($command);
246
247 This method returns the plugin (module) for the given command. If no
248 plugin implements the command, it returns false.
249
250 get_command
251 my ($command_name, $opt, @args) = $app->get_command(@args);
252
253 Process arguments and into a command name and (optional) global
254 options.
255
256 usage
257 print $self->app->usage->text;
258
259 Returns the usage object for the global options.
260
261 usage_desc
262 The top level usage line. Looks something like
263
264 "yourapp <command> [options]"
265
266 global_opt_spec
267 Returns a list with help command unless "no_help_plugin" has been
268 specified or an empty list. Can be overridden for pre-dispatch option
269 processing. This is useful for flags like --verbose.
270
271 usage_error
272 $self->usage_error("Something's wrong!");
273
274 Used to die with nice usage output, during "validate_args".
275
277 • publish and bring in Log::Speak (simple quiet/verbose output)
278
279 • publish and use our internal enhanced describe_options
280
281 • publish and use our improved simple input routines
282
284 Ricardo Signes <rjbs@semiotic.systems>
285
287 • Adam Prime <aprime@oanda.com>
288
289 • ambs <ambs@cpan.org>
290
291 • Andreas Hernitscheck <andreash@lxhe.(none)>
292
293 • A. Sinan Unur <nanis@cpan.org>
294
295 • Chris 'BinGOs' Williams <chris@bingosnet.co.uk>
296
297 • David Golden <dagolden@cpan.org>
298
299 • David Steinbrunner <dsteinbrunner@pobox.com>
300
301 • Davor Cubranic <cubranic@stat.ubc.ca>
302
303 • Denis Ibaev <dionys@gmail.com>
304
305 • Diab Jerius <djerius@cfa.harvard.edu>
306
307 • Glenn Fowler <cebjyre@cpan.org>
308
309 • Ingy dot Net <ingy@ingy.net>
310
311 • Jakob Voss <jakob@nichtich.de>
312
313 • Jakob Voss <voss@gbv.de>
314
315 • Jérôme Quelin <jquelin@gmail.com>
316
317 • John SJ Anderson <genehack@genehack.org>
318
319 • Karen Etheridge <ether@cpan.org>
320
321 • Kent Fredric <kentfredric@gmail.com>
322
323 • Lucas Theisen <ltheisen@mitre.org>
324
325 • Matthew Astley <mca@sanger.ac.uk>
326
327 • mokko <mauricemengel@gmail.com>
328
329 • Olivier Mengué <dolmen@cpan.org>
330
331 • Ryan C. Thompson <rct@thompsonclan.org>
332
333 • Salvatore Bonaccorso <carnil@debian.org>
334
335 • Sergey Romanov <sromanov-dev@yandex.ru>
336
337 • Stephan Loyd <stephanloyd9@gmail.com>
338
339 • Stephen Caldwell <steve@campusexplorer.com>
340
341 • Yuval Kogman <nuffin@cpan.org>
342
344 This software is copyright (c) 2021 by Ricardo Signes.
345
346 This is free software; you can redistribute it and/or modify it under
347 the same terms as the Perl 5 programming language system itself.
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351perl v5.34.0 2022-01-20 App::Cmd(3)