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&Rest Lists
- To: jeff%aiva.edinburgh.ac.uk@nss.cs.ucl.ac.uk
- Subject: &Rest Lists
- From: Jon L White <edsel!jonl@labrea.Stanford.EDU>
- Date: Thu, 7 Apr 88 23:53:51 PDT
- Cc: Common-Lisp@sail.stanford.edu, @relay.cs.net:ELIOT@cs.umass.edu
- In-reply-to: Jeff Dalton's message of Sat, 2 Apr 88 18:54:38 bst <29307.8804021754@aiva.ed.ac.uk>
re: > FOO is a null function needed to prevent optimization.
> (dotimes (i 10000000) (cons 1 2)) is optimized to:
> (dotimes (i 10000000) nil) so:
Why isn't it optimized to just NIL?
Conjecture: it is an easy optimization to notice that a side-effect-free
function is being called in a place where no values are expected back (i.e.,
the call is only "for effects"); but it is much harder to have an analyzer
for tagbodies which usefully notices that they "don't do anything".
-- JonL --
- References:
- Re: &Rest Lists
- From: Jeff Dalton <jeff%aiva.edinburgh.ac.uk@NSS.Cs.Ucl.AC.UK>