# ABSTRACT: Specify how sub accepts arguments
1;
=pod
=head1 NAME
Sub::Spec::Clause::args_as - Specify how sub accepts arguments
=head1 VERSION
version 1.0.0
=head1 SYNOPSIS
# the default, sub accept %args ($args{arg1}, $args{arg2}, and so on)
args_as => 'HASH'
# sub accepts @args (($arg1, $arg2, ...))
args_as => 'ARRAY'
# sub accepts $args object ($args->arg1, $args->arg2, and so on)
args_as => 'OBJECT'
=head1 DESCRIPTION
NOTE: Currently only args_as 'HASH' is supported by the various Sub::Spec
modules, as they can work without any wrapper.
=head2 args_as => ARRAY
Setting args_as to 'ARRAY' is useful if you have a "legacy" sub which accepts
arguments directly from @_, like most normal Perl subs.
$SPEC{is_palindrome} = {
summary => 'Check whether a string is a palindrome',
args => {str => 'str*', ci=>[bool=>{default=>0}]},
args_as => 'ARRAY',
result => 'bool*',
};
sub is_palindrome {
my ($str, $ci) = @_;
$str = lc($str) if $ci;
[200, "OK", $str eq reverse($str) ? 1:0];
}
XXX How should special arguments be passed? Via localized %special_args?
When importing, you can select argument passing style (HASH, HASHREF, ARRAY,
ARRAYREF):
# XXX use, say, args_passing? so it's not confused with args_as because they
# are slightly different (as is result_naked from spec side and exporter side)
use My::Palindrome is_palindrome => {args_as=>'ARRAY', result_naked=>1};
say is_palindrome('abc'); # 0
say is_palindrome('abA'); # 0
say is_palindrome('abA', 1); # 1
=head2 args_as => OBJECT
Setting args_as to 'OBJECT' is useful if you want to catch typo mistakes in your
subs:
package My::Palindrome;
$SPEC{is_palindrome} = {
summary => 'Check whether a string is a palindrome',
args => {str => 'str*', ci=>[bool=>{default=>0}]},
args_as => 'OBJECT',
result => 'bool*',
};
sub is_palindrome {
# XXX or should it even like in Dancer? args->str et al?
my $args = shift;
my $str = $args->str;
$str = lc($str) if $args->ci;
[200, "OK", $str eq reverse($str) ? 1:0];
}
How this works: An argument class will be created for this sub (say
Sub::Spec::__arg::My::Palindrome::is_palindrome) which has accessors for every
defined argument in the specification (as well as special arguments).
Special arguments are accessed via _NAME (like $args->_undo, $args->_reverse,
etc) so make sure you do not define arguments with those names if you want to
use object argument passing.
=head1 SEE ALSO
L<Sub::Spec>
L<Sub::Spec::Exporter>
=head1 AUTHOR
Steven Haryanto <stevenharyanto@gmail.com>
=head1 COPYRIGHT AND LICENSE
This software is copyright (c) 2011 by Steven Haryanto.
This is free software; you can redistribute it and/or modify it under
the same terms as the Perl 5 programming language system itself.
=cut
__END__