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Re: requiring proper tail recursion
Date: Tue, 02 Sep 1997 10:13:25 -0500
From: William D Clinger <will@ccs.neu.edu>
...
There is another difficulty with this definition of proper tail
recursion: In some implementations, CALL-WITH-CURRENT-CONTINUATION
changes the representation of a continuation in ways that make it
occupy additional space. Furthermore repeated uses of CALL/CC to
capture the same continuation might create multiple copies. Both
kinds of implementation of CALL/CC are forbidden by the following
definition of proper tail recursion.
But your original message of Mon, 02 Jun 1997 proposed:
2. Define proper tail recursion in terms of the asymptotic
space used by continuations.
Doesn't the term `asymptotic' allow an implementation to consume space
for continuations, so long as those continuations can be collected?
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