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Data::OptList(3)      User Contributed Perl Documentation     Data::OptList(3)

NAME
       Data::OptList - parse and validate simple name/value option pairs

VERSION
       version 0.110

SYNOPSIS
	 use Data::OptList;

	 my $options = Data::OptList::mkopt([
	   qw(key1 key2	key3 key4),
	   key5	=> { ... },
	   key6	=> [ ... ],
	   key7	=> sub { ... },
	   key8	=> { ... },
	   key8	=> [ ... ],
	 ]);

       ...is the same thing, more or less, as:

	 my $options = [
	   [ key1 => undef,	   ],
	   [ key2 => undef,	   ],
	   [ key3 => undef,	   ],
	   [ key4 => undef,	   ],
	   [ key5 => { ... },	   ],
	   [ key6 => [ ... ],	   ],
	   [ key7 => sub { ... },  ],
	   [ key8 => { ... },	   ],
	   [ key8 => [ ... ],	   ],
	 ]);

DESCRIPTION
       Hashes are great	for storing named data,	but if you want	more than one
       entry for a name, you have to use a list	of pairs.  Even	then, this is
       really boring to	write:

	 $values = [
	   foo => undef,
	   bar => undef,
	   baz => undef,
	   xyz => { ...	},
	 ];

       Just look at all	those undefs!  Don't worry, we can get rid of those:

	 $values = [
	   map { $_ => undef } qw(foo bar baz),
	   xyz => { ...	},
	 ];

       Aaaauuugh!  We've saved a little	typing,	but now	it requires thought to
       read, and thinking is even worse	than typing... and it's	got a bug!  It
       looked right, didn't it?	 Well, the "xyz	=> { ... }" gets consumed by
       the map,	and we don't get the data we wanted.

       With Data::OptList, you can do this instead:

	 $values = Data::OptList::mkopt([
	   qw(foo bar baz),
	   xyz => { ...	},
	 ]);

       This works by assuming that any defined scalar is a name	and any
       reference following a name is its value.

FUNCTIONS
   mkopt
	 my $opt_list =	Data::OptList::mkopt($input, \%arg);

       Valid arguments are:

	 moniker	- a word used in errors	to describe the	opt list; encouraged
	 require_unique	- if true, no name may appear more than	once
	 must_be	- types	to which opt list values are limited (described	below)
	 name_test	- a coderef used to test whether a value can be	a name
			  (described below, but	you probably don't want	this)

       This produces an	array of arrays; the inner arrays are name/value
       pairs.  Values will be either "undef" or	a reference.

       Positional parameters may be used for compatibility with	the old
       "mkopt" interface:

	 my $opt_list =	Data::OptList::mkopt($input, $moniker, $req_uni, $must_be);

       Valid values for	$input:

	undef	 -> []
	hashref	 -> [ [	key1 =>	value1 ] ... ] # non-ref values	become undef
	arrayref -> every name followed	by a non-name becomes a	pair: [	name =>	ref ]
		    every name followed	by undef becomes a pair: [ name	=> undef ]
		    otherwise, it becomes [ name => undef ] like so:
		    [ "a", "b",	[ 1, 2 ] ] -> [	[ a => undef ],	[ b => [ 1, 2 ]	] ]

       By default, a name is any defined non-reference.	 The "name_test"
       parameter can be	a code ref that	tests whether the argument passed it
       is a name or not.  This should be used rarely.  Interactions between
       "require_unique"	and "name_test"	are not	yet particularly elegant, as
       "require_unique"	just tests string equality.  This may change.

       The "must_be" parameter is either a scalar or array of scalars; it
       defines what kind(s) of refs may	be values.  If an invalid value	is
       found, an exception is thrown.  If no value is passed for this
       argument, any reference is valid.  If "must_be" specifies that values
       must be CODE, HASH, ARRAY, or SCALAR, then Params::Util is used to
       check whether the given value can provide that interface.  Otherwise,
       it checks that the given	value is an object of the kind.

       In other	words:

	 [ qw(SCALAR HASH Object::Known) ]

       Means:

	 _SCALAR0($value) or _HASH($value) or _INSTANCE($value,	'Object::Known')

   mkopt_hash
	 my $opt_hash =	Data::OptList::mkopt_hash($input, $moniker, $must_be);

       Given valid "mkopt" input, this routine returns a reference to a	hash.
       It will throw an	exception if any name has more than one	value.

EXPORTS
       Both "mkopt" and	"mkopt_hash" may be exported on	request.

AUTHOR
       Ricardo Signes <rjbs@cpan.org>

CONTRIBUTORS
       o   Olivier MenguA(C) <dolmen@cpan.org>

       o   Ricardo SIGNES <rjbs@codesimply.com>

COPYRIGHT AND LICENSE
       This software is	copyright (c) 2006 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 v5.24.1			  2016-03-25		      Data::OptList(3)

NAME | VERSION | SYNOPSIS | DESCRIPTION | FUNCTIONS | EXPORTS | AUTHOR | CONTRIBUTORS | COPYRIGHT AND LICENSE

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