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base(3pm)                             Perl Programmers Reference Guide                             base(3pm)



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



perl v5.8.8                                      2001-09-21                                        base(3pm)