How many modules have you run across that do this?

package Foo;
our @ISA = qw(Bar);

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I believe that clobbering @ISA is wrong (though I'm occasionally guilty of it myself). The problem arises in that we sometimes may not know how @ISA has been modified before we clobber it. This is highly unlikely in the example above, but it could be an issue in a more complex class. Even if our current class won't give us problems, future changes could create problems.

Fortunatly, the use base pragma is just as easy to code for:

package Foo;
use base 'Bar';

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base will take care of munging @ISA for us, and has the additional effect of requireing the inherited package for us.

So please, leave @ISA alone. It might feel good, but it could bite you in the long run.

----
I wanted to explore how Perl's closures can be manipulated, and ended up creating an object system by accident.
-- Schemer

Note: All code is untested, unless otherwise stated

In reply to Avoiding the Use of @ISA = qw(Foo::Bar); by hardburn

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