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Re: PDD 2, vtables

From:
Nicholas Clark
Date:
February 7, 2001 10:12
Subject:
Re: PDD 2, vtables
Message ID:
20010207181218.M63724@plum.flirble.org
On Wed, Feb 07, 2001 at 05:54:14PM +0000, David Mitchell wrote:
> Well, many of the vtable methods are operator-ish rather than value-ish,
> presumably on the grounds of efficiency. A pure 'value' vtable wouldnt
> have add(), concatenate() etc. Whihc leads me back to: I'm not sure
> whether you are in favour of, or oppose, += etc being vtable methods.

I'm not either. They feel like they should be operators.
But I don't like the thought of going in and out of a lot of generic
routines for

$a = 3;
$a += 2;

when the integer scalar ought to know what the inside of another integer
scalar looks like, and that 2 + 3 doesn't overflow.

Hmm. += isn't another opcode
it's a special case of a = b + c where the PMCs for a and b are the same
thing. And I see no real reason why it can't be part of the + entry.


Nicholas Clark

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