1App::Cmd::Command::helpU(s3e)r Contributed Perl DocumentaAtpipo:n:Cmd::Command::help(3)
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NAME

6       App::Cmd::Command::help - display a command's help screen
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VERSION

9       version 0.335
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DESCRIPTION

12       This command will either list all of the application commands and their
13       abstracts, or display the usage screen for a subcommand with its
14       description.
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PERL VERSION

17       This library should run on perls released even a long time ago.  It
18       should work on any version of perl released in the last five years.
19
20       Although it may work on older versions of perl, no guarantee is made
21       that the minimum required version will not be increased.  The version
22       may be increased for any reason, and there is no promise that patches
23       will be accepted to lower the minimum required perl.
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USAGE

26       The help text is generated from three sources:
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28       •   The "usage_desc" method
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30       •   The "description" method
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32       •   The "opt_spec" data structure
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34       The "usage_desc" method provides the opening usage line, following the
35       specification described in Getopt::Long::Descriptive.  In some cases,
36       the default "usage_desc" in App::Cmd::Command may be sufficient and you
37       will only need to override it to provide additional command line usage
38       information.
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40       The "opt_spec" data structure is used with Getopt::Long::Descriptive to
41       generate the description of the options.
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43       Subcommand classes should override the "discription" method to provide
44       additional information that is prepended before the option
45       descriptions.
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47       For example, consider the following subcommand module:
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49         package YourApp::Command::initialize;
50
51         # This is the default from App::Cmd::Command
52         sub usage_desc {
53           my ($self) = @_;
54           my $desc = $self->SUPER::usage_desc; # "%c COMMAND %o"
55           return "$desc [DIRECTORY]";
56         }
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58         sub description {
59           return "The initialize command prepares the application...";
60         }
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62         sub opt_spec {
63           return (
64             [ "skip-refs|R",  "skip reference checks during init", ],
65             [ "values|v=s@",  "starting values", { default => [ 0, 1, 3 ] } ],
66           );
67         }
68
69         ...
70
71       That module would generate help output like this:
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73         $ yourapp help initialize
74         yourapp initialize [-Rv] [long options...] [DIRECTORY]
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76         The initialize command prepares the application...
77
78               --help            This usage screen
79               -R --skip-refs    skip reference checks during init
80               -v --values       starting values
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AUTHOR

83       Ricardo Signes <cpan@semiotic.systems>
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86       This software is copyright (c) 2022 by Ricardo Signes.
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88       This is free software; you can redistribute it and/or modify it under
89       the same terms as the Perl 5 programming language system itself.
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93perl v5.36.0                      2023-01-19        App::Cmd::Command::help(3)
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