[Date Prev][Date Next][Thread Prev][Thread Next][Date Index][Thread Index]
Re: define and set! with multiple-values
- To: Scott_Fahlman@SEF-PMAX.SLISP.CS.CMU.EDU
- Subject: Re: define and set! with multiple-values
- From: John D. Ramsdell <email@example.com>
- Date: Thu, 31 Dec 92 15:53:58 EST
- Cc: firstname.lastname@example.org, info-dylan@CAMBRIDGE.APPLE.COM
- In-reply-to: Your message of "Thu, 31 Dec 92 15:01:22 EST." <9212312009.AA02013@brazil.cambridge.apple.com>
- Posted-date: Thu, 31 Dec 92 15:53:58 EST
> From: Scott_Fahlman@SEF-PMAX.SLISP.CS.CMU.EDU
> Multiple values do make life *much* harder for implementors.
In Scheme implementations with compilers that use continuation-passing
conversion, a return of some number of values is transformed into an
application of the continuation to the return values, i.e., just
another procedure call. Multiple values do not make life harder for
those implementations. One of the reasons some people would like to
make sure that extra return values are not silently ignored is because
it allows implementations to use the same calling mechanism for both
calls and returns.
By the way, I like multiple return values is Scheme--I'm one of the
ones who lead the fight to have them accepted in Scheme's next revision!