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NAME

Return::DataButBool - Return a boolean value that also has arbitrary numeric and string values

VERSION

This document describes Return::DataButBool version 0.0.3

SYNOPSIS

    use Return::DataButBool;

    sub whatever {
            ...
            return $ok ? data_but_true( $count ) : data_but_false( $count, $error );
    }

later in the code using this function:

    my $total = 0;
    for my $thing ( @stuff ) {
            my $rc = whatever( $thing );
            $total += $rc; # numeric value
        
            if( !$rc ) { # boolean value
                    carp "Error happened: $rc"; # string value
            }
    }

DESCRIPTION

Perl's Zero-But-True ( 0e0 ) is a most handy tool (See String::ZeroButTrue). This module expands on that idea by having a return value that has different boolean, numeric, and string values.

For example you could return a count of files processed (say 42 which is "true") but still say it failed in boolean context.

or you could return any false value ( not just '0' ) but still return true. The flexibility allows for all sorts of use.

EXPORT

All 3 functions are exported by default.

INTERFACE

The data_but_* functions take one or two arguments.

The first is the numeric value. Can be signed and/or decimal if you like. If its not [+-] digit [decimal digit] then it is passed through int() - see _get_num_from()

The second is the string value. If not specified the numeric value is used.

zero_but_true()

takes no args, returns good 'ol 0e0 (zero but true). See String::ZeroButTrue for more comprehensive alternatives.

data_but_true()

The value returned evaluates to true in a boolean context. The numeric and string context are determined by the arguments passed as describe above.

data_but_false()

The value returned evaluates to false in a boolean context. The numeric and string context are determined by the arguments passed as describe above.

Internal functions

_get_num_from()

This function makes sure your first argument is numeric ( possible sign, digits, possihle decimal point more digits - or int() )

DIAGNOSTICS

Throws no errors or warnings

CONFIGURATION AND ENVIRONMENT

Return::DataButBool requires no configuration files or environment variables.

DEPENDENCIES

This uses the excellent Contextual::Return whcih can be used if your return needs are more complicated than this module's purpose.

INCOMPATIBILITIES

None reported.

BUGS AND LIMITATIONS

No bugs have been reported.

Please report any bugs or feature requests to bug-return-databutbool@rt.cpan.org, or through the web interface at http://rt.cpan.org.

AUTHOR

Daniel Muey <http://drmuey.com/cpan_contact.pl>

LICENCE AND COPYRIGHT

Copyright (c) 2007, Daniel Muey <http://drmuey.com/cpan_contact.pl>. All rights reserved.

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

DISCLAIMER OF WARRANTY

BECAUSE THIS SOFTWARE IS LICENSED FREE OF CHARGE, THERE IS NO WARRANTY FOR THE SOFTWARE, TO THE EXTENT PERMITTED BY APPLICABLE LAW. EXCEPT WHEN OTHERWISE STATED IN WRITING THE COPYRIGHT HOLDERS AND/OR OTHER PARTIES PROVIDE THE SOFTWARE "AS IS" WITHOUT WARRANTY OF ANY KIND, EITHER EXPRESSED OR IMPLIED, INCLUDING, BUT NOT LIMITED TO, THE IMPLIED WARRANTIES OF MERCHANTABILITY AND FITNESS FOR A PARTICULAR PURPOSE. THE ENTIRE RISK AS TO THE QUALITY AND PERFORMANCE OF THE SOFTWARE IS WITH YOU. SHOULD THE SOFTWARE PROVE DEFECTIVE, YOU ASSUME THE COST OF ALL NECESSARY SERVICING, REPAIR, OR CORRECTION.

IN NO EVENT UNLESS REQUIRED BY APPLICABLE LAW OR AGREED TO IN WRITING WILL ANY COPYRIGHT HOLDER, OR ANY OTHER PARTY WHO MAY MODIFY AND/OR REDISTRIBUTE THE SOFTWARE AS PERMITTED BY THE ABOVE LICENCE, BE LIABLE TO YOU FOR DAMAGES, INCLUDING ANY GENERAL, SPECIAL, INCIDENTAL, OR CONSEQUENTIAL DAMAGES ARISING OUT OF THE USE OR INABILITY TO USE THE SOFTWARE (INCLUDING BUT NOT LIMITED TO LOSS OF DATA OR DATA BEING RENDERED INACCURATE OR LOSSES SUSTAINED BY YOU OR THIRD PARTIES OR A FAILURE OF THE SOFTWARE TO OPERATE WITH ANY OTHER SOFTWARE), EVEN IF SUCH HOLDER OR OTHER PARTY HAS BEEN ADVISED OF THE POSSIBILITY OF SUCH DAMAGES.