Re: use base peculiarities

[andreas.koenig@anima.de (Andreas J. Koenig)]

>>>>> On Wed, 19 Jan 2000 11:27:02 -0700, Tom Christiansen <tchrist@chthon.perl.com> said:

 > Why does base.pm not use %ISA to decide whether to require?  Why

You mean @ISA, not %ISA, right?

 > does it use the package's $VERSION variable instead?  This seems
 > to lead to its seting that variable to the bizarre "-1, set by
 > base.pm", which isn't even "0 but true" (why isn't it?).  Seems to 
 > me that merely abiding by %ISA would be much clearer.  

Is it possible that you confuse the inheritant and the inheritee? @ISA
is defined in the package that inherits, not (necessarily) in the
package we inherit from.

 > The archives have some messages about this from Sarathy, Andreas, 
 > Kurt, and Tim.  For example:

 > http://www.xray.mpe.mpg.de/mailing-lists/perl5-porters/1999-05/msg00811.html
 > http://www.xray.mpe.mpg.de/mailing-lists/perl5-porters/1999-03/msg01050.html

 > Another issue beyond the peculiar disregard for %INC is that base.pm
 > conflates the notion of "base package" with physical files in its
 > cavalier assumption that every base package must be in its own file.
 > For example, this doesn't allow for the fact that one file may
 > simultaneously define symbols in multiple package namespaces, as
 > we see in Tie/Hash.pm, or as was whilom seen in IO/Socket.pm
 > defining IO::Socket::{INET,UNIX}.

The disregard of %INC is due to the very fact that you describe.
*Because* a "base package" doesn't imply the existance of a physical
file, base.pm cannot take %INC into account.

-- 
andreas

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Follow-Ups from:

Gurusamy Sarathy <gsar@ActiveState.com>

References to:

Tom Christiansen <tchrist@chthon.perl.com>

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