Perl pragma to declare constants
Perl Perl 6
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NAME

constant::tiny - Perl pragma to declare constants

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.

INSTALLATION

To install this module, run the following commands:

perl Makefile.PL
make
make test
make install

Alternatively, to install with Module::Build, you can use the following commands:

perl Build.PL
./Build
./Build test
./Build install

SUPPORT

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

perldoc constant::tiny

You can also look for information at:

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.