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Getopt-Kingpin-0.10
River stage one • 3 direct dependents • 3 total dependents
9 ++
/ Getopt::Kingpin

NAME

Getopt::Kingpin - command line options parser (like golang kingpin)

SYNOPSIS

    use Getopt::Kingpin;
    my $kingpin = Getopt::Kingpin->new;
    $kingpin->flags->get("help")->short('h');
    my $verbose = $kingpin->flag('verbose', 'Verbose mode.')->short('v')->bool;
    my $name    = $kingpin->arg('name', 'Name of user.')->required->string;

    $kingpin->parse;

    # perl sample.pl hello
    printf "name : %s\n", $name;

Automatically generate --help option.

    usage: script.pl [<flags>] <name>

    Flags:
      -h, --help     Show context-sensitive help.
      -v, --verbose  Verbose mode.

    Args:
      <name>  Name of user.

Support sub-command.

    use Getopt::Kingpin;
    my $kingpin = Getopt::Kingpin->new;

    my $register      = $kingpin->command('register', 'Register a new user.');
    my $register_nick = $register->arg('nick', 'Nickname for user.')->required->string;
    my $register_name = $register->arg('name', 'Name for user.')->required->string;

    my $post       = $kingpin->command('post', 'Post a message to a channel.');
    my $post_image   = $post->flag('image', 'Image to post.')->file;
    my $post_channel = $post->arg('channel', 'Channel to post to.')->required->string;
    my $post_text    = $post->arg('text', 'Text to post.')->string_list;

    my $cmd = $kingpin->parse;

    if ($cmd eq 'register') {
        printf "register %s %s\n", $register_nick, $register_name;
    } elsif ($cmd eq 'post') {
        printf "post %s %s %s\n", $post_image, $post_channel, @{$post_text->value};
    } else {
        $kingpin->help;
    }

Help is below.

    usage: script.pl [<flags>] <command> [<args> ...]

    Flags:
      --help  Show context-sensitive help.

    Commands:
      help [<command>...]
        Show help.

      register [<nick>] [<name>]
        Register a new user.

      post [<flags>] [<channel>] [<text>]
        Post a message to a channel.

DESCRIPTION

Getopt::Kingpin is a command line parser. It supports flags and positional arguments.

  • Simple to use

  • Automatically generate help flag (--help).

This module is inspired by Kingpin written in golang. https://github.com/alecthomas/kingpin

METHOD

new()

Create a parser object. Default script-name is basename($0).

    my $kingpin = Getopt::Kingpin->new;
    my $kingpin = Getopt::Kingpin->new("script-name.pl", "description of script");
    my $kingpin = Getopt::Kingpin->new(
        name        => "script-name.pl",
        description => "description of script",
    );

    # Use hash ref to set description only.
    my $kingpin = Getopt::Kingpin->new({
        description => "description of script",
    });

flag($name, $description)

Add and return Getopt::Kingpin::Flag object.

    # Define --debug option
    my $debug = $kingpin->flag("debug", "Enable debug mode.");

    # Set $debug to boolean value
    $debug->bool;

    # shorthand
    my $debug = $kingpin->flag("debug", "Enable debug mode.")->bool;

Getopt::Kingpin::Flag object has methods below.

value()

Get flag value.

    my $name = $kingpin->flag("name", "Set name.")->string;

    # perl script.pl --name 'kingpin'
    printf "%s\n", $name->value;  # -> kingpin

    # simple way
    printf "%s\n", $name;  # -> kingpin

short()

Set short flag.

    # Define --debug and -d
    my $debug = $kingpin->flag("debug", "Enable debug mode.")->short('-d')->bool;

default()

The default value can be overridden with the default($value).

    # Set default value to true (1)
    my $debug = $kingpin->flag("debug", "Enable debug mode.")->default(1)->bool;

The default can be set to a coderef or object overloading &{}.

    my $debug = $kingpin->flag("debug", "Enable debug mode.")->default(sub {
      my $config = read_config_files();
      return $config->{DEBUG};
    })->bool;

override_default_from_envar()

The default value can be overridden with the override_default_from_envar($envar).

    # Set default value to environment value of __DEBUG__
    # export $__DEBUG__=1 to enable debug mode
    my $debug = $kingpin->flag("debug", "Enable debug mode.")->override_default_from_envar("__DEBUG__")->bool;

required()

Set required.

    my $debug = $kingpin->flag("debug", "Enable debug mode.")->required->bool;

placeholder()

Set placeholder value for flag in the help. Here are some examples of flags with various permutations.

    --name=NAME        # flag("name")->string
    --name="Harry"     # flag("name")->default("Harry")->string
    --name=FULL-NAME   # flag("name")->placeholder("FULL-NAME")->string

hidden()

If set hidden(), flag does not appear in the help.

types

bool()

Boolean value. (0 or 1) Boolean flag has a negative complement: --<name> and --no-<name>.

    # --debug or --no-debug
    my $debug = $kingpin->flag("debug")->bool;

existing_dir()

Path::Tiny object.

existing_file()

Path::Tiny object.

existing_file_or_dir()

Path::Tiny object.

file()

Path::Tiny object.

int()

Integer value.

num()

Numeric value.

string()

String value. It is default type to flag.

string_list(), int_list(), file_list(), etc

Allows repeated uses of a flag.

  --input=customers.csv --input=customers2.csv

string_hash(), int_hash(), file_hash(), etc

Allows repeated use of a flag as key-value pairs.

  --define os=linux --define arch=x86_64

arg($name, $description)

Add and return Getopt::Kingpin::Arg object.

    my $name = $kingpin->arg("name", "Set name")->string;

Getopt::Kingpin::Arg object has methods below. Below are same as Flag's.

value()

Get value.

default()

Set default value.

override_default_from_envar()

Set default value by environment variable.

required()

Set required.

command()

Add sub-command.

    my $post    = $kingpin->command("post", "post image");

parse()

Parse @arguments. If @arguments is empty, parse @ARGV.

    # parse @ARGV
    $kingpin->parse;

    # parse @arguments
    $kingpin->parse(@arguments);

If define sub-command, parse() return Getopt::Kingpin::Command object;

    my $kingpin = Getopt::Kingpin->new();
    my $post    = $kingpin->command("post", "post image");
    my $server  = $post->arg("server", "")->string();
    my $image   = $post->arg("image", "")->file();

    my $cmd = $kingpin->parse;
    printf "cmd : %s\n", $cmd;
    printf "cmd : %s\n", $cmd->name;

You may also pass an arrayref to parse():

    $kingpin->parse( \@arguments );

An empty arrayref will not cause Kingpin to parse @ARGV like an empty array would.

_parse()

Parse @_. Internal use only.

version($version)

Set application version to $version.

help_short()

Internal use only.

help()

Print help.

SEE ALSO

LICENSE

Copyright (C) sago35.

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

AUTHOR

sago35 <sago35@gmail.com>