These question suggest that there are some basics about Perl OO that you're missing. You might want to see Perl Object Oriented Meta-Tutorial for pointers to where to start. For example, to subclass, you'd need to make sure the argument to base is in quotes: 

use base 'MathML::Entities';

[download]

However, for your question about making functions available, you just need to make sure the functions are imported in the first place, and then specify them to be exported. For that, you have to do it longhand, you can't use base as that doesn't import any functions.

package MathML::Entities::Approximate;
use strict;
use MathML::Entities qw(function1 function2); # import the desired fun
+ctions
use vars qw( @ISA @EXPORT );
@ISA = qw( MathML::Entities Exporter);
@EXPORT = qw( function1 function2 ); # re-export them

[download]

Unfortunately, to the last point, if %ENTITIES is a "my" variable in MathML::Entities, you can't access it directly without "breaking the rules" using something like PadWalker.

-xdg

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In reply to Re: Modifying/extending a superclass' data by xdg
in thread Modifying/extending a superclass' data by kiz

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