Re: [Jscheme-user] apply/2 vs apply/n (absent): apply takes only 2 arguments

[Ken A. <kan...@bb...>]

I've found this version of apply annoying myself.
I've just checked in changes so that apply now takes 1 or more arguments,=
=20
the last of which must be a list.  I have not changed the documentation.

BTW, Tim, your definition of list* relies on (null? (rest '()) -> #t
which it is in Jscheme, but it is an error in Scheme in general.

k

At 01:14 PM 6/18/2002, Timothy Hickey wrote:

>On Tuesday, June 18, 2002, at 03:57 AM, Hoehle, Joerg-Cyril wrote:
>
>>Hi,
>>
>>apply in Jscheme takes exactly 2 arguments.
>>>apply
>>{jsint.Primitive apply[2]}
>>
>>In R4RS terms:
>>   essential procedure: apply proc args
>>   procedure: apply proc arg1 ... args
>>, this means that only the essential part if implemented in Jscheme.
>>
>>R5RS' apply takes n arguments and doesn't make a distinction anymore.=20
>>Having only apply/2 is a nightmare for recursive procedures with variab=
le=20
>>number of arguments.
>>
>>BTW, the documentation at
>>http://jscheme.sourceforge.net/jscheme/doc/R4RSprimitives.html
>>is inconsistent. It says
>>(apply f arguments ) ...
>>(map F L) ...
>>Yet map takes n arguments (in both R4RS and R5RS and) in Jscheme.
>>
>>
>>While it is a trivial exercise to write an apply/n based on the apply/2=
,
>
>You can load in a file newapply.scm that redefines apply:
>
>(set! apply
>   (let ((ap apply))
>     (letrec ((list*(lambda (R) (if (null? (rest R)) (first R) (cons=20
> (first R) (list* (rest R)))))))
>        (lambda (f . R)
>         (ap f (list* R))))))
>
>
>>  it is not so w.r.t. compiler optimization and inlining.
>For the future this may be an issue. For the moment, the Jscheme compile=
r=20
>does not
>make use of much optimization or inlining.
>
>>Will the home-grown apply/n compile to as efficient code/bytecode as ap=
ply/2?
>For now yes, but in the future no.
>>
>>BTW, Common Lisp has list* which is quite useful for a straightforward=20
>>apply/n->apply/2.
>
>You have a point, perhaps we should add list* and apply/n to Jscheme...
>---Tim---
>
>>
>>Regards,
>>         J=F6rg H=F6hle.
>>Using Jscheme 5.0 04/05/2002 on MS-Woes-2000
>>
>>-----------------------------------------------------------------------=
-----
>>                    Bringing you mounds of caffeinated joy
>>>>>     http://thinkgeek.com/sf    <<<
>>
>>_______________________________________________
>>Jscheme-user mailing list
>>Jsc...@li...
>>https://lists.sourceforge.net/lists/listinfo/jscheme-user
>
>
>------------------------------------------------------------------------=
----
>                   Bringing you mounds of caffeinated joy
>                      >>>     http://thinkgeek.com/sf    <<<
>
>_______________________________________________
>Jscheme-user mailing list
>Jsc...@li...
>https://lists.sourceforge.net/lists/listinfo/jscheme-user
>