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use strict;
use warnings;
package System::Sub::AutoLoad;
$System::Sub::AutoLoad::VERSION = '0.162800';
use System::Sub ();
sub _croak
{
require Carp;
goto &Carp::croak
}
# Storage for sub options until they are installed with the AUTOLOAD
my %AutoLoad;
sub import
{
my $pkg = caller;
shift;
while (@_) {
my $name = shift;
_croak "invalid arg: SCALAR expected" unless defined ref $name && ! ref $name;
my $fq_name = $pkg.'::'.$name;
$AutoLoad{$fq_name} = shift if @_ && ref $_[0];
# Create a forward declaration that will be usable by the Perl
# parser. See subs.pm
no strict 'refs';
*{$fq_name} = \&{$fq_name};
}
# Install the AUTOLOAD sub
no strict 'refs';
*{$pkg.'::AUTOLOAD'} = \&_AUTOLOAD;
}
sub _AUTOLOAD
{
my $fq_name = our $AUTOLOAD;
my $options = delete $AutoLoad{$fq_name};
System::Sub->import($fq_name, $options ? ($options) : ());
no strict 'refs';
goto &$fq_name
}
1;
__END__
=head1 NAME
System::Sub::AutoLoad - Auto-wrap external commands as DWIM subs
=head1 VERSION
version 0.162800
=head1 SYNOPSIS
=head2 Basic usage
Any unknown sub will become a C<L<System::Sub>>.
use System::Sub::AutoLoad;
my $hostname = hostname();
=head2 Usage with forward declaration
Allows to avoid using parentheses. C<L<System::Sub>> import stays lazy.
use System::Sub::AutoLoad qw(hostname);
my $hostname = hostname;
=head2 Usage with forward declaration command options
Options definitions will be checked lazily at the first call to the AUTOLOAD
for that sub.
use System::Sub::AutoLoad hostname => [ 0 => '/bin/hostname' ];
my $hostname = hostname;
=head1 DESCRIPTION
Any unknown sub in your code will be transformed into a C<L<System::Sub>> at its
first call. This is L<lazy|http://en.wikipedia.org/wiki/Lazy_evaluation> import
for C<L<System::Sub>>.
To avoid using parentheses after the sub name, you usually have to predeclare
the sub with either a forward declaration (a sub without body such as
C<sub foo;>) or with the C<L<subs|subs>> module. With C<L<Sytem::Sub::AutoLoad>>
you can simply list the subs names on the C<use> line and that will be done
for you.
You can also pass C<L<System::Sub>> options to the sub, but they will be lazily
analysed: this is the full C<L<System::Sub>> power, but with lazy import.
=head2 Implementation details
This module exports an L<AUTOLOAD|perlsub/Autoloading> sub that will import
the sub with C<L<System::Sub>> at its first call.
=head1 AUTHOR
Olivier MenguE<eacute>, C<dolmen@cpan.org>.
=head1 COPYRIGHT & LICENSE
Copyright E<copy> 2012 Olivier MenguE<eacute>.
This library is free software; you can redistribute it and/or modify it under
the same terms as Perl 5 itself.
=cut
# vim:set et sw=4 sts=4:
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