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- To: barmar@Think.COM
- Subject: &REST lists
- From: Glenn S. Burke <gsb@JASPER.Palladian.COM>
- Date: Wed, 6 Jan 88 22:25 EST
- Cc: firstname.lastname@example.org
- In-reply-to: <880105105957.3.BARMAR@OCCAM.THINK.COM>
- Reply-to: Glenn S. Burke <GSB%Jasper@LIVE-OAK.LCS.MIT.EDU>
Date: Tue, 5 Jan 88 10:59 EST
From: Barry Margolin <barmar@Think.COM>
Date: Tue, 5 Jan 88 02:12 EST
From: Glenn S. Burke <email@example.com>
I think it is legal for APPLY to pass user-specified list structure to
the function; if so the &REST list should be treated as read-only, as it
well might be.
That doesn't follow. Just because you pass a read-only list to APPLY
doesn't mean that it has to use that same list when it invokes the
function. APPLY could COPY-LIST it. Or in an implementation that uses
stack-consed &REST args the list elements might be copied to the stack.
You miss the point entirely. I am saying that if it is a permissible
implementation for apply to NOT copy a user-specified list, then proper
coding practice would be to not modify &rest lists.
I don't know or remember if APPLY is permitted to do this. This came up
back when the original stack-list/heap-list decision was made, and there
may have been a consensus on it at the time.