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Re: restricted hashes, and other readonlyness (was "clamp...")

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From:
Graham Barr
Date:
November 5, 2001 09:38
Subject:
Re: restricted hashes, and other readonlyness (was "clamp...")
Message ID:
20011105173840.N53751@pobox.com
On Mon, Nov 05, 2001 at 09:10:45AM +0000, Nick Ing-Simmons wrote:
> Graham Barr <gbarr@pobox.com> writes:
> >> >      Net::FTP object
> >>
> >> A possible - Graham care to comment?
> >
> >the only classes I can think of where you would want to restrict the keys
> >are ones where you want to prohibit sub-classes.
> 
> I am assuming that either the base-class's "new" asks the class what
> its keys are, or new is overriden in the subclass:

I don't see the point in imposing that. I agree that resticted hashes have
thier place. But I don't agree that object must use it.

Graham.

> 
> sub new
> {
>  my ($class,...) = @_;
>  my %self;
>  allowed($class->permitted_keys);
>  ...
> }
> 
> 
> >Net::FTP is a sub-class
> >of IO::Socket::INET, so IO::Socket::INET cannot be restricted and I have
> >seen people sub-class Net::FTP too.
> >
> >Graham.
> --
> Nick Ing-Simmons
> http://www.ni-s.u-net.com/
> 
> 

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