/ 
constant-tiny-1.02
River stage zero No dependents
/ constant::tiny

NAME

constant::tiny - Perl pragma to declare constants

SYNOPSIS

use constant::tiny;
use constant PI    => 4 * atan2(1, 1);
use constant DEBUG => 0;

print "Pi equals ", PI, "...\n" if DEBUG;

DESCRIPTION

This module is a lightweight version of the Perl standard module constant.pm. Here are the keys differences:

  • only works on Perl 5.10+ in order to simplify a good part of the code

  • doesn't support Unicode names; please use the standard constant.pm module if you need to create constants with Unicode names

  • stricter rules about valid names, only allow names with alphanums ([a-zA-Z0-9] and underscore (_), allowing one optional leading underscore

In order to simplify its usage, constant:tiny uses the normal constant API. The main advatange is that switching your code to constant::tiny means simply adding it before the first use constant. The disadvantage is that, obviously, both modules can't be used at the same time. If the normal constant was loaded before constant::tiny, the latter won't do anything, letting the normal constant do the work.

Other than this, the usage is (nearly) exactly the same as with the standard constant module. For more details, please read constant.

Rationale

The original reason to write this module was that, starting with version 1.24, constant always loaded utf8_heavy.pl, which consumes some memory. Usually, this is not problematic, but in some particular cases (embedded Perl, frequently forked programs à la CGI), the increased memory cost can become a concern.

Therefore, this module was written as a alternative solution, with no support for Unicode names, so that programs working in memory constrained environments could have a better control.

Funnily enough, the day constant::tiny was released on CPAN (the code had been written two months earlier as a proof of concept), Brad Gilbert proposed a patch for constant in order to delay loading utf8_heavy.pl until necessary.

Therefore constant::tiny is less useful (which is good news), but can still address specific needs, if you want to restrict constant names to alphanums only.

SUPPORT

You can find documentation for this module with the perldoc command.

perldoc constant::tiny

You can also look for information at:

BUGS

Please report any bugs or feature requests to contant-tiny at rt.cpan.org, or through the web interface at https://rt.cpan.org/Public/Dist/Display.html?Name=constant-tiny. I will be notified, and then you'll automatically be notified of progress on your bug as I make changes.

ACKNOWLEDGEMENTS

This module is heavily based on constant.pm, originaly written by Tom Phoenix, Casey West, Nicholas Clark, Zefram and many other folks from the Perl 5 Porters.

AUTHOR

Sébastien Aperghis-Tramoni <sebastien at aperghis.net>

LICENSE

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