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App::Cmd::Command::helUser Contributed Perl DocumentApp::Cmd::Command::help(3)

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

VERSION
       version 0.334

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

PERL VERSION SUPPORT
       This module has a long-term perl	support	period.	 That means it will
       not require a version of	perl released fewer than five years ago.

       Although	it may work on older versions of perl, no guarantee is made
       that the	minimum	required version will not be increased.	 The version
       may be increased	for any	reason,	and there is no	promise	that patches
       will be accepted	to lower the minimum required perl.

USAGE
       The help	text is	generated from three sources:

       o   The "usage_desc" method

       o   The "description" method

       o   The "opt_spec" data structure

       The "usage_desc"	method provides	the opening usage line,	following the
       specification described in Getopt::Long::Descriptive.  In some cases,
       the default "usage_desc"	in App::Cmd::Command may be sufficient and you
       will only need to override it to	provide	additional command line	usage
       information.

       The "opt_spec" data structure is	used with Getopt::Long::Descriptive to
       generate	the description	of the options.

       Subcommand classes should override the "discription" method to provide
       additional information that is prepended	before the option
       descriptions.

       For example, consider the following subcommand module:

	 package YourApp::Command::initialize;

	 # This	is the default from App::Cmd::Command
	 sub usage_desc	{
	   my ($self) =	@_;
	   my $desc = $self->SUPER::usage_desc;	# "%c COMMAND %o"
	   return "$desc [DIRECTORY]";
	 }

	 sub description {
	   return "The initialize command prepares the application...";
	 }

	 sub opt_spec {
	   return (
	     [ "skip-refs|R",  "skip reference checks during init", ],
	     [ "values|v=s@",  "starting values", { default => [ 0, 1, 3 ] } ],
	   );
	 }

	 ...

       That module would generate help output like this:

	 $ yourapp help	initialize
	 yourapp initialize [-Rv] [long	options...] [DIRECTORY]

	 The initialize	command	prepares the application...

	       --help		 This usage screen
	       -R --skip-refs	 skip reference	checks during init
	       -v --values	 starting values

AUTHOR
       Ricardo Signes <rjbs@semiotic.systems>

COPYRIGHT AND LICENSE
       This software is	copyright (c) 2021 by Ricardo Signes.

       This is free software; you can redistribute it and/or modify it under
       the same	terms as the Perl 5 programming	language system	itself.

perl v5.32.1			  2021-06-19	    App::Cmd::Command::help(3)

NAME | VERSION | DESCRIPTION | PERL VERSION SUPPORT | USAGE | AUTHOR | COPYRIGHT AND LICENSE

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