[plt-scheme] Bindings for list primitives in 4.0.1

From: Marco Morazan (morazanm at gmail.com)
Date: Thu Jul 3 19:15:22 EDT 2008

Thanks! That explains it. --Marco

On Thu, Jul 3, 2008 at 6:54 PM, Carl Eastlund <cce at ccs.neu.edu> wrote:
> PLT Scheme 4.0 did away with mutable pairs in the default libraries.
> They are in a separate library now - not just in the sense of r6rs,
> where the mutators are in a separate library, but in that the pairs of
> the default library can never be mutated, and the mutable-pairs
> library therefore has a different kind of pairs.  Other languages
> (such as EOPL, r5rs, r6rs, and legacy mzscheme) retain their mutable
> pairs, and therefore use the primitives from the mutable pairs
> library.
>
> Matthew made a long blog post about all of this last November,
> hopefully it can shed some light on the design decision:
>
> http://blog.plt-scheme.org/2007/11/getting-rid-of-set-car-and-set-cdr.html
>
> --Carl
>
> On Thu, Jul 3, 2008 at 6:44 PM, Marco Morazan <morazanm at gmail.com> wrote:
>> Dear All,
>>
>> My apologizes for the flurry of inquiries.......
>>
>> I start-up DrScheme and depending on the language selected the list
>> primitives are bound differently (see examples below). Is that the
>> intended behavior? I would guess not, but is there a quick fix around
>> it?
>>
>> Thanks,
>>
>> Marco
>>
>>
>> Welcome to DrScheme, version 4.0.1tsrj2008-1 [3m].
>> Language: Pretty Big (includes MrEd and Advanced Student); memory
>> limit: 128 megabytes.
>>> car
>> #<procedure:car>
>>> cdr
>> #<procedure:cdr>
>>> cons
>> #<procedure:cons>
>>> map
>> #<procedure:map>
>>>
>>
>> -------------------------------
>>
>> Welcome to DrScheme, version 4.0.1tsrj2008-1 [3m].
>> Language: R5RS; memory limit: 128 megabytes.
>>> car
>> #<procedure:mcar>
>>> cdr
>> #<procedure:mcdr>
>>> cons
>> #<procedure:mcons>
>>> map
>> #<procedure:mmap>
>>>
>>
>> -----------------------------------
>>
>> Welcome to DrScheme, version 4.0.1tsrj2008-1 [3m].
>> Language: Essentials of Programming Languages (2nd ed.); memory limit:
>> 128 megabytes.
>>> car
>> #<procedure:mcar>
>>> cdr
>> #<procedure:mcdr>
>>> cons
>> #<procedure:mcons>
>>> map
>> #<procedure:mmap>
>>>
>>
>> ------------------------------------------
>


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