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CONTENTS

NAME

base - Establish IS-A relationship with base classes at compile time

SYNOPSIS

package Baz;
use base qw(Foo Bar);

DESCRIPTION

Allows you to both load one or more modules, while setting up inheritance from those modules at the same time. Roughly similar in effect to

package Baz;
BEGIN {
    require Foo;
    require Bar;
    push @ISA, qw(Foo Bar);
}

If any of the listed modules are not loaded yet, base silently attempts to require them (and silently continues if the require failed). Whether to require a base class module is determined by the absence of a global variable $VERSION in the base package. If $VERSION is not detected even after loading it, <base> will define $VERSION in the base package, setting it to the string -1, set by base.pm.

Will also initialize the fields if one of the base classes has it. Multiple inheritence of fields is NOT supported, if two or more base classes each have inheritable fields the 'base' pragma will croak. See fields, public and protected for a description of this feature.

DIAGNOSTICS

Base class package "%s" is empty.

base.pm was unable to require the base package, because it was not found in your path.

HISTORY

This module was introduced with Perl 5.004_04.

CAVEATS

Due to the limitations of the implementation, you must use base before you declare any of your own fields.

SEE ALSO

fields