/ 
true-0.18
River stage two • 21 direct dependents • 49 total dependents
/ true

NAME

true - automatically return a true value when a file is required

SYNOPSIS

package Contemporary::Perl;

use strict;
use warnings;
use true;

sub import {
    strict->import();
    warnings->import();
    true->import();
}

DESCRIPTION

Perl's require builtin (and its use wrapper) requires the files it loads to return a true value. This is usually accomplished by placing a single

1;

statement at the end of included scripts or modules. It's not onerous to add but it's a speed bump on the Perl novice's road to enlightenment. In addition, it appears to be a non-sequitur to the uninitiated, leading some to attempt to mitigate its appearance with a comment:

1; # keep require happy

or:

1; # Do not remove this line

or even:

1; # Must end with this, because Perl is bogus.

This module packages this "return true" behaviour so that it need not be written explicitly. It can be used directly, but it is intended to be invoked from the import method of a Modern::Perl-style module that enables modern Perl features and conveniences and cleans up legacy Perl warts.

METHODS

true is file-scoped rather than lexically-scoped. Importing it anywhere in a file (e.g. at the top-level or in a nested scope) causes that file to return true, and unimporting it anywhere in a file restores the default behaviour. Redundant imports/unimports are ignored.

import

Enable the "automatically return true" behaviour for the currently-compiling file. This should typically be invoked from the import method of a module that loads true. Code that uses this module solely on behalf of its callers can load true without importing it e.g.

use true (); # don't import

sub import {
    true->import();
}

1;

But there's nothing stopping a wrapper module also importing true to obviate its own need to explicitly return a true value:

use true; # both load and import it

sub import {
    true->import();
}

# no need to return true

unimport

Disable the "automatically return true" behaviour for the currently-compiling file.

EXPORT

None by default.

NOTES

Because some versions of YAML::XS may interpret the key of true as a boolean, you may have trouble declaring a dependency on true.pm. You can work around this by declaring a dependency on the package true::VERSION, which has the same version as true.pm.

SEE ALSO

AUTHOR

chocolateboy, <chocolate@cpan.org>

COPYRIGHT AND LICENSE

Copyright (C) 2010-2011 by chocolateboy

This library is free software; you can redistribute it and/or modify it under the same terms as Perl itself, either Perl version 5.10.0 or, at your option, any later version of Perl 5 you may have available.