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Re: Destructive operations
- To: edsel!babel!eb@navajo.stanford.edu (Eric Benson)
- Subject: Re: Destructive operations
- From: Timothy.Freeman@theory.cs.cmu.edu
- Date: Wed, 07 Jan 1987 15:37:00 -0000
- Cc: common-lisp@sail.stanford.edu, gross@sam.cs.cmu.edu
- In-reply-to: <8701070049.AA00286@blacksox.edsel.uucp>
Because the compiler is permitted to share structure with constants in
compiled code, it follows that modifying such a constant is illegal.
Pardon me for being thick-headed, but I just don't see why this is
true. I would be willing to say that "Because the compiler is
permitted to share structure with constants in compiled code,
modifying such a constant destructively may have the side effect of
modifying any or all other constants which are equal to the given
constant". This would allow one to conclude that modifying such a
constant is a bad idea, but not that it is illegal.
I agree that it ought to be illegal, but I don't see how CLtL implies
that it is illegal.