Ray Dillinger scripsit:

> The only semantics for which this is the "correct" behavior
> are pure-functional promises, ie, computations with no side
> effects.

Indeed.  Still, that's not hay; pure functional computations may be
well worth delaying.  In the Pure language (which is about as pure as
ML -- the name has nothing to do with pure functional programming),
most but not all standard procedures are auto-forcing.  This allows
clean interoperation between streams and lists.  See
http://docs.pure-lang.googlecode.com/hg/pure.html#lazy-evaluation-and-streams
for some elementary examples.

As far as I know, Chibi is the only Scheme with auto-forcing, and it
must be turned on by a configuration option.

--
John Cowan   cowan@ccil.org    http://ccil.org/~cowan
Original line from The Warrior's Apprentice by Lois McMaster Bujold:
"Only on Barrayar would pulling a loaded needler start a stampede toward one."
English-to-Russian-to-English mangling thereof: "Only on Barrayar you risk to
lose support instead of finding it when you threat with the charged weapon."

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