Perl module: Difference between revisions

Revision as of 07:45, 19 May 2009

Revision as of 09:09, 19 May 2009

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<source lang="perl">

# "package" givesis the namespace where the module's will reside infunctionality/data andresides. also

# It dictates the name of the file if you want it to be "use"d.

# If more than one word, it constrains the ___location of the module.

package Hello::World;

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# By default Perl allows you to use variables without declaring

# them. While thisThis may be convenient for short scripts and one-liners.

# one-liners,But in a longer unit of code such as a module it is wise to declare your variables

# your variables both to catch typos and to keep them from beingconstrain accessibletheir outside

# accessibility appropriately from outside the module. The strict pragma

# forces you to declare your variables.

use strict;

# Similarly, Perl does not issue warningsmost bycompiler default.or run-time Awarnings module,by beingdefault.

# moreMore complicated thanscripts, asuch script,as usuallymost modules, will usually find them very helpful

# helpful for debugging. The warnings pragma turns on optional warnings.

use warnings;

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use base 'Exporter';

# ExportWhen the module is invoked, export, by default, the function "hello" into the namespace of

# anythe codenamespace whichof usesthe thisusing modulecode.

our @EXPORT = qw(hello);

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This is a procedural module which gives you the famous "Hello, world!"

message, and itsit’s even customizable!

=head2 Functions