base

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



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 inheri-
       tance 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 v5.8.6                       2001-09-21                           base(3)