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Re: **DRAFT** issue CONSTANT-COLLAPSING
- To: email@example.com
- Subject: Re: **DRAFT** issue CONSTANT-COLLAPSING
- From: Jeff Dalton <jeff%aiai.edinburgh.ac.uk@NSS.Cs.Ucl.AC.UK>
- Date: Mon, 9 Jan 89 19:00:05 GMT
- In-reply-to: Sandra J Loosemore's message of Sat, 7 Jan 89 11:48:52 MST
> There is little reason why implementations should not be allowed to
> perform more general collapsing of structures, since the arguments
> against doing so also apply to collapsing of EQUAL structures, which
> is already permitted.
There's a problem with this rationale. Arguments against individual
cases might also apply to EQUAL structures, but an argument that there
should be *some* non-coalescable structures is different. I might
say, well, EQUAL sturctures is OK because I still have vectors, etc.
Removing all the alternatives requires more than arguments against
each one individually.
> Cost to users:
> It is hard to imagine a program that would break under this proposal.
As I've said before, I think it's trivial to imagine a program that
would break. Just think of one that assumes only EQUAL structures
will be collapsed.