NAME

Getopt::LL - Flexible argument processing.

VERSION

This document describes Getopt::LL version 1.0.0

SYNOPSIS

    use Getopt:LL qw(getoptions);

    my $use_foo = 0;

    my $options = getoptions({
        '-t'            => 'string',
        '--verbose|-v'  => 'flag',
        '--debug|-d'    => 'digit',
        '--use-foo'     => sub {
            $use_foo = 1;
        },
        '-output|-o'    => sub {
            my ($getopt, $node) = @_;
            my $next_arg = $getopt->get_next_arg($node);

            if ($next_arg eq '-') {
                $out_to_stdout = 1;
            }

            return $next_arg;
        };
    });

DESCRIPTION

Getopt::LL provides several ways for defining the arguments you want. There is Getopt::LL::Simple for defining arguments on the -use-line-, Getopt::LL::Short for abbreviated rules (that looks like Getopt::Long).

RULES

-Rules- is the guidelines Getopt::LL follows when it meets new options. The rules defines what options we want, which options are required, and what to do with an option.

A simple rule-set could be written like this:

my $rules = {
    '-foo'      => 'string',
    '-bar'      => 'string',
    '--verbose' => 'digit',
    '--debug'   => 'flag',
};

Rule types/actions.

The argument to an rule is what we call a rule type or rule action. It can be one of the following:

  • 'flag'

The option is a flag. The value of the option will be boolean true.

  • 'string'

The option is a string. The value of the option will be the next argument in the argument list.

  • 'digit'

The option is a number. The value of the option will be the next argument in the argument list. The value will be sent to is_digit($value) to check that it's really a number. If it's not a number and the die_on_type_mismatch option is set, the program will die with a type mismatch error message.

A digit can also be a hex value if it begins with -0x-, any hex value will be converted to a decimal value.

  • A regular expression: qr/ /

The next argument will be matched against the regular expression. If it doesn't match the program will die with the message

Argument [--arg] doesn't match [regular-expression].
  • An anonymous subroutine. sub { }

The sub-routine will be called with the following arguments

  1. $_[0] - The Getopt::LL object.

  2. $_[1] - The current argument node (A Getopt::LL::DLList::Node] object).

  3. $_[2] - The argument name.

  4. $_[3] - If an argument value was set by the user with --arg=value, the value is in this variable.

The return value of the anonymous subroutine will be the value of the option.

Here is an example of a rule sub that simply assigns the value of the next argument to the option value:

    my $rules = {

        '-foo'  => sub {
            my ($getopt, $node, $arg_name, $arg_value) = @_;
                return $arg_value if $arg_value;

                my $next_arg = $getopt->get_next_arg($node);

                return $next_arg;
        },
    };

    my $result = getoptions($rules);

    print 'FOO IS: [', $result->{'-foo'}, "]\n";

if this program is called with the arguments: -foo bar or -foo=bar it will print out this message:

FOO IS [bar]

Specifying required arguments.

There are two ways of specifying required arguments.

  • Embedded in the rule name, by an exclamation point !.

my $rules = {
    '-foo!' => 'string',
};
  • Or by adding the required flag.

my $rules = {
    '-foo'  => {
        type        => 'string',
        required    => 1,
    },
}

Adding default values to non-required arguments.

There are two ways of specifying default values.

  • Embedded in the rule name, inside parens ( .. )

my $rules = {
    '-bar(defaultValue)' => 'string',
};
  • Or by adding a default key to the spec.

my $rules = {
    '-bar'  => {
        type    => 'string',
        default => 'defaultValue',
    },
};

DID YOU SAY SIMPLE?

With Getopt::LL::Simple you can define the arguments you want on the -use-line-:

    #!/usr/bin/perl
    use strict;
    use warnings;

    # we have three arguments:
    #   -f!          (our filename, which is a s(tring) the ! means that it's
    #               a required argument.
    #   --verbose   (print extra information about what we're doing, is a flag).
    #   --debug     (the level of debugging information to print. is a
    #                d(igit).
    #
    use Getopt::LL::Simple qw(
        -f!=s
        --verbose
        --debug|d=d
    );

    if ($ARGV{'--verbose'}) {
        print "In verbose mode...\n";
    }

    if ($ARGV{'--debug'}) {
        print 'Debugging level is set to: ', $ARGV{'--debug'}, "\n";
    }

    print "The contents of @ARGV is:\n";
    prnit "\t", join{q{, }, @ARGV), "\n";

The options that was found is placed into %ARGV, the arguments that is not an option is placed into @ARGV. So say we have run the program with the following arguments:

./myprogram -f tmp.log --verbose --debug=3 foo bar

or

./myprogram -f tmp.log --verbose --debug 3 foo bar

it will give this output:

In verbose mode...
Debugging level is set to: 3
The contents of @ARGV is:
    foo, bar 

SUBROUTINES/METHODS

CONSTRUCTOR

new(\%rules, \%options, \@opt_argv )

Uses @ARGV if no \@opt_argv is present.

ATTRIBUTES

rules

set_rules

The list of rules passed to new.

options

set_options

The options passed to new.

dll

set_dll

Our arguments converted to a doubly linked list. (is a Getopt::LL::DLList object).

result

set_result

The final argument hash.

leftovers

set_leftovers

Array of items in the argument list that does not start with - or --.

INSTANCE METHODS

parseoption($argument, $node)

This method is called for each argument to decide what to do with it.

find_arg_type($argument)

Find out what kind of argument this is.

If the argument starts with - (a single dash) it returns short, but if it starts with -- (two dashes) it returns long.

is_string($value, $option_name)

Check if value is a proper string.

is_digit($value, $option_name)

Check if value is a digit. (0-9+) If value starts with -0x-, it is treated as a hex value.

type_mismatch_error($type, $message)

Called whenever a type does not match it's requirements.

unknown_argument_error($argument)

Called when a argument that has no rule is found. (turn off by setting the allow_unspecified option to a true value).

handle_rule($option_name, $rule, $node)

Called when parseoption() finds an argument that we have an existing rule for. This function decides what to do with the argument based on it's RULE_ACTION.

get_next_arg($node)

Get and delete the next argument. (Gets the next node in our doubly linked list and deletes the current node)

peek_next_arg($node)

Look at the next argument, but don't delete it.

get_prev_arg($node)

Get and delete the previous argument.

peek_prev_arg($node)

Look at the previous argument, but don't delete it.

delete_arg($node)

Deletes the argument.

rules_prepare(\%rules)

Find and prepare aliases in the rule set.

rules_postactions( )

Things to do with rules after argument processing is done. Like adding default values for arguments with default values defined and checking for required arguments.

show_help( )

Print help for arguments to standard error. This is experimental and the implementation is not exactly complete.

show_usage( )

Print usage to standard error. This is experimental and the implementation is not exactly complete.

CLASS METHODS

getoptions(\%rules, \%options, \@opt_argv)

Parses and gets arguments based on the rules in \%rules. Uses @ARGV if \@opt_arg is not specified.

Returns hash with the arguments it found. @ARGV is replaced with the arguments that does not start with - or --.

opt_String($help_for_option)

Shortcut for writing:

{
    type => 'string',
    help => $help_for_option,
}

opt_Digit($help_for_option)

Shortcut for writing:

{
    type => 'digit',
    help => $help_for_option,
}

opt_Flag($help_for_option)

Shortcut for writing:

{
    type => 'flag',
    help => $help_for_option,
}

PRIVATE INSTANCE METHODS

_init()

Called by new to traverse and parse the doubly linked list of arguments.

_warn(@messages)

Print a warning on the screen, but only if $options->{silent} is not set.

PRIVATE CLASS METHODS

_regex_as_text($regex)

Quoted regexes are not very user-friendly to print directly, so this function turns a quoted regex like:

(?xmsi:hello)

into:

/hello/xmsii

DIAGNOSTICS

CONFIGURATION AND ENVIRONMENT

This module requires no configuration file or environment variables.

DEPENDENCIES

INCOMPATIBILITIES

None known.

BUGS AND LIMITATIONS

No bugs have been reported.

Please report any bugs or feature requests to bug-getopt-ll@rt.cpan.org, or through the web interface at CPAN Bugtracker.

SEE ALSO

TEST SUITE CODE COVERAGE

---------------------------- ------ ------ ------ ------ ------ ------ ------
File                           stmt   bran   cond    sub    pod   time  total
---------------------------- ------ ------ ------ ------ ------ ------ ------
lib/Getopt/LL.pm              100.0   98.6   94.4  100.0  100.0   38.2   99.2
lib/Getopt/LL/DLList.pm       100.0  100.0  100.0  100.0  100.0   15.1  100.0
lib/Getopt/LL/DLList/Node.pm  100.0  100.0    n/a  100.0  100.0    9.9  100.0
lib/Getopt/LL/Short.pm        100.0  100.0  100.0  100.0  100.0    1.4  100.0
lib/Getopt/LL/Simple.pm       100.0  100.0  100.0  100.0    n/a    0.6  100.0
...topt/LL/SimpleExporter.pm  100.0  100.0    n/a  100.0  100.0    4.6  100.0
lib/Getopt/LL/properties.pm   100.0  100.0    n/a  100.0    n/a   30.2  100.0
Total                         100.0   99.0   96.2  100.0  100.0  100.0   99.6
---------------------------- ------ ------ ------ ------ ------ ------ ------

The summary was generated by Devel::Cover.

AUTHOR

Ask Solem, C<< ask@0x61736b.net >>.

LICENSE AND COPYRIGHT

Copyright (c), 2007 Ask Solem C<< ask@0x61736b.net >>.

All rights reserved.

This library is free software; you can redistribute it and/or modify it under the same terms as Perl itself, either Perl version 5.8.6 or, at your option, any later version of Perl 5 you may have available.

DISCLAIMER OF WARRANTY

BECAUSE THIS SOFTWARE IS LICENSED FREE OF CHARGE, THERE IS NO WARRANTY FOR THE SOFTWARE, TO THE EXTENT PERMITTED BY APPLICABLE LAW. EXCEPT WHEN OTHERWISE STATED IN WRITING THE COPYRIGHT HOLDERS AND/OR OTHER PARTIES PROVIDE THE SOFTWARE "AS IS" WITHOUT WARRANTY OF ANY KIND, EITHER EXPRESSED OR IMPLIED, INCLUDING, BUT NOT LIMITED TO, THE IMPLIED WARRANTIES OF MERCHANTABILITY AND FITNESS FOR A PARTICULAR PURPOSE. THE ENTIRE RISK AS TO THE QUALITY AND PERFORMANCE OF THE SOFTWARE IS WITH YOU. SHOULD THE SOFTWARE PROVE DEFECTIVE, YOU ASSUME THE COST OF ALL NECESSARY SERVICING, REPAIR, OR CORRECTION.

IN NO EVENT UNLESS REQUIRED BY APPLICABLE LAW OR AGREED TO IN WRITING WILL ANY COPYRIGHT HOLDER, OR ANY OTHER PARTY WHO MAY MODIFY AND/OR REDISTRIBUTE THE SOFTWARE AS PERMITTED BY THE ABOVE LICENSE, BE LIABLE TO YOU FOR DAMAGES, INCLUDING ANY GENERAL, SPECIAL, INCIDENTAL, OR CONSEQUENTIAL DAMAGES ARISING OUT OF THE USE OR INABILITY TO USE THE SOFTWARE (INCLUDING BUT NOT LIMITED TO LOSS OF DATA OR DATA BEING RENDERED INACCURATE OR LOSSES SUSTAINED BY YOU OR THIRD PARTIES OR A FAILURE OF THE SOFTWARE TO OPERATE WITH ANY OTHER SOFTWARE), EVEN IF SUCH HOLDER OR OTHER PARTY HAS BEEN ADVISED OF THE POSSIBILITY OF SUCH DAMAGES.

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