NAME

Getopt::EX - Getopt Extender

DESCRIPTION

Getopt::EX extends the basic function of Getopt family to support user-definable option aliases, and dynamic module which works together with the script through option interface.

INTERFACES

There are two major interfaces to use Getopt::EX modules.

Easy one is Getopt::Long compatible module, Getopt::EX::Long. You can simply replace module declaration and get the benefit of this module to some extent. It allows user to make start up rc file in their home directory, which provide user-defined option aliases.

Use Getopt::EX::Loader to get full capabilities. Then the user of your script can make their own extension module which work together with original command through command option interface.

Another module Getopt::EX::Colormap is made to produce colored text on ANSI terminal, and to provide easy way to maintain labeled colormap table and option handling. It can be used just like Term::ANSIColor but you'd better use standard module in that case.

Getopt::EX::Long

This is the easiest way to get started with Getopt::EX. This module is almost compatible with Getopt::Long and replaceable.

In addition, if the command name is example,

~/.examplerc

file is loaded by default. In this rc file, user can define their own option with macro processing. This is useful when the command takes complicated arguments. User can also define default option which is used always. For example,

option default -n

gives option -n always when the script executed. See Getopt::EX::Module document what you can do in this file.

If the rc file includes a section start with __PERL__, it is evaluated as a perl program. User can define any kind of functions there, which can be invoked from command line option if the script is aware of them.

Also, special command option preceded by -M is taken and corresponding perl module is loaded. For example,

% example -Mfoo

will load App::example::foo module.

This module is normal perl module, so user can write anything they want. If the module option come with initial function call, it is called at the beginning of command execution. Suppose that the module foo is specified like this:

% example -Mfoo::bar(buz=100) ...

Then, after the module foo is loaded, function bar is called with the parameter baz with value 100.

If the module includes __DATA__ section, it is interpreted just same as rc file. So you can define arbitrary option there. Combined with startup function call described above, it is possible to control module behavior by user defined option.

Getopt::EX::Loader

This module provides more primitive access to the underlying modules. You should create loader object first:

use Getopt::EX::Loader;
my $loader = new Getopt::EX::Loader
    BASECLASS => 'App::example';

Then load rc file:

$loader->load_file("$ENV{HOME}/.examplerc");

And process command line options:

$loader->deal_with(\@ARGV);

Finally gives built-in function declared in dynamically loaded modules to option parser.

my $parser = new Getopt::Long::Parser;
$parser->getoptions( ... , $loader->builtins )

Actually, this is what Getopt::EX::Long module is doing internally.

To communicate with user-defined subroutines, use Getopt::EX::Func module, which provide parse_func interface. If your script has --begin option which tells the script to call specific function at the beginning of execution. Write something like:

use Getopt::EX::Func qw(parse_func);
GetOptions("begin:s" => $opt_begin);
my $func = parse_func($opt_begin);
$func->call;

Then the script can be invoked like this:

% example -Mfoo --begin 'repeat(debug,msg=hello,count=2)'

See Getopt::EX::Func for more detail.

Getopt::EX::Colormap

This module is not so tightly coupled with other modules in Getopt::EX. It provides concise way to specify ANSI terminal 256 colors with various effects, and produce terminal sequences by color specification or label parameter.

You can use this with normal Getopt::Long:

my @opt_colormap;
use Getopt::Long;
GetOptions("colormap|cm=s" => \@opt_colormap);

my %colormap = ( # default color map
    FILE => 'R',
    LINE => 'G',
    TEXT => 'B',
    );
my @colors;

require Getopt::EX::Colormap;
my $handler = new Getopt::EX::Colormap
    HASH => \%colormap,
    LIST => \@colors;

$handler->load_params(@opt_colormap);

and then get colored string as follows.

print $handler->color("FILE", "FILE in Red\n");
print $handler->color("LINE", "LINE in Blue\n");
print $handler->color("TEXT", "TEXT in Green\n");

In this example, user can change these colors from command line option like this:

% example --colormap FILE=C,LINE=M,TEXT=Y

or call arbitrary perl function like:

% example --colormap FILE='sub{uc}'

Above example produces uppercase version of provided string instead of ANSI color sequence.

If you only use coloring function, it's more simple:

require Getopt::EX::Colormap;
my $handler = new Getopt::EX::Colormap;

print $handler->color("R", "FILE in Red\n");
print $handler->color("G", "LINE in Blue\n");
print $handler->color("B", "TEXT in Green\n");

or even simpler non-oo interface:

use Getopt::EX::Colormap qw(colorize);

print colorize("R", "FILE in Red\n");
print colorize("G", "LINE in Blue\n");
print colorize("B", "TEXT in Green\n");

AUTHOR

Kazumasa Utashiro

COPYRIGHT

The following copyright notice applies to all the files provided in this distribution, including binary files, unless explicitly noted otherwise.

Copyright 2015-2018 Kazumasa Utashiro

LICENSE

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