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GFUJI / PerlIO-code-0.03 / lib / PerlIO / code.pm 

            

              
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package PerlIO::code;
use 5.008_001;
use strict;
our $VERSION = '0.03';
use XSLoader;
XSLoader::load(__PACKAGE__, $VERSION);
1;
__END__
=head1 NAME
PerlIO::code - Calls a subroutine with I/O interface
=head1 VERSION
This document describes PerlIO::code version 0.03
=head1 SYNOPSIS
        use PerlIO::code; # need to say explicitly
        # make an input filter
        open my $in, '<', sub{ uc scalar <> };
        print while <$in>;
        # make an output filter
        open my $out, '>', sub{ print uc shift };
        print $out while <>;
        # it accepts an extra argument
        sub my_readline{
                my($fh) = @_;
                my $line = <$fh>;
                # ...filterling...
                return $line;
        }
        open my $fh, '<', \&my_readline, \*STDIN;
=head1 DESCRIPTION
C<PerlIO::code> helps to make an simple I/O filter. It is easier than C<tie>,
but provides very limited functions. All it can do is to do C<readline()>
and C<print()>.
=head1 NOTES
=over 4
=item *
For some reason, the actual layer name of C<PerlIO::code> is C<:Code>, not C<:code>.
=item *
C<PerlIO::code> is slower than the C<tie> interface.
=item *
C<< open my $in, '<', sub{ "foo" }; my $s = <$in>; >> makes an endless loop, because
the internal C<readline> routine reads C<$in> on until reaching C<EOF>, which
is never reached.
=back
=head1 CONFIGURATION AND ENVIRONMENT
No configuration files or environment variables.
=head1 DEPENDENCIES
Perl 5.8.1 or later, and a C compiler.
=head1 BUGS AND LIMITATIONS
No bugs have been reported.
Please report any bugs or feature requests to
C<bug-perlio-code@rt.cpan.org>, or through the web interface at
L<http://rt.cpan.org/>.
=head1 SEE ALSO
L<PerlIO::Util>.
L<Tie::Handle>.
L<PerlIO::via>.
L<PerlIO>.
=head1 AUTHOR
Goro Fuji E<lt>gfuji(at)cpan.orgE<gt>.
=head1 LICENCE AND COPYRIGHT
Copyright (c) 2008, Goro Fuji E<lt>gfuji(at)cpan.orgE<gt>. Some rights reserved.
This module is free software; you can redistribute it and/or
modify it under the same terms as Perl itself. See L<perlartistic>.
=cut