bug in for on pre59 built with clisp using cygwin

Dear all,

I have found the reason of the bug that Dan Stanger has encountered.
This is somewhat a complex bug for which I can propose several solutions.

Let's take an example which will be used through out the explanation.
for u in [1,2,3] do print(u);
1
2
3

This does not work in clisp2.27 and the latest maxima. Because the
word 'in' is not properly converted to the symbol $IN.

The function bothcase-implode defined in commac.lisp performs this
conversion. For the keyword 'in', the conversion takes place in the
following way: (#(J\(B$ #(J\(Bi #(J\(Bn) -> |$in| -> $IN . The logic in this function
works only when the symbol |$in| does not exist for the first time this
function was called with (#(J\(B$ #(J\(Bi #(J\(Bn) as its input. That first time,
(setf (get sym 'upcase) symup) is executed only if the symbol |$in|
does not exist. Second time and later when the function is called
with (#(J\(B$ #(J\(Bi #(J\(Bn) as its input, 'upcase' property is used to do the
right conversion.

The above condition does hold for symbols such as |$for|, |$do| and
|$print|. However, it does NOT hold for |$in|. That causes the conversion
not to work for keyword 'in'. So, who defines this symbol?

If you take a look at mactex.lisp, then you see a function texmdoin
definition is:

(defun texmdoin (x)
   (nconc `("(J\\(Bmathbf{for}" ,(second x) $|in| ,(third x))
          (cond ((sixth x) `("(J\\(Bmathbf{thru}" ,(sixth x))))
          (cond ((null (seventh x)) nil)
                ((eq 'mnot (caar (seventh x)))
                 `("(J\\(Bmathbf{while}" ,(cadr (seventh x))))
                (t `("(J\\(Bmathbf{unless}" ,(seventh x))))
          `("(J\\(Bmathbf{do}" ,(eighth x))))

You see a symbol $|in| there in the definition. This symbol is same as
|$in|. This means that once mactex.{lisp,fas} is read, the symbol starts
to exist. To confirm, you may change $|in| to something like |$anything|
and reload the file. Then the example
for u in [1,2,3] do print(u);
does work fine. (Oh, of course this is not a solution since generated tex
source will be mangled.)

So, some solutions are:
(1) to modify texmdoin in mactex.lisp to avoid using a lisp symbol to
generate a TeX source text. It should be achievable only using strings.

(2) to modify bothcase-implode in commac.lisp so that it does not care
the prior existence of a symbol such as |$in|.

(3) In some place, just execute (setf (get '|$in| 'upcase) '$IN) so that
the logic in bothcase-implode works and conversion takes place.

I would suggest (3) for a temporary solution and do a serious rewrite
of bothcase-implode function later at some time. Any suggestions?

Some note:
- Though bessel.lisp defines function name $in, the symbol $in and
|$in| are different and bessel.lisp has nothing to do with this bug.

- Vadim V. Zhytnikov has pointed out that GCL performs things well.
This may have something to do with the how common lisp symbol
intern works on GCL and clisp. Since I don't have GCL at hand and
Mac OS X is not a supported platform for GCL, I cannot test it.
It would be of some help if someone do:
(eql '|$in| '$|in|)
and tell me the result.

Yasuaki Honda
Chiba, Japan.

On 2001.12.23, at 22:43, Vadim V. Zhytnikov wrote:

> This is certainly clisp specific bug. With gcl
> all variants
> for ... in ...
> for ... IN ...
> for ... iN ...
> for ... In ...
> work fine.
>
> Yasuaki Honda wrote:
>
>> Dear Dr. Dan Stanger,
>>
>> I just noticed that:
>>         for u IN x do print(u);
>> works fine while
>>         for u in x do print(u);
>> does not.
>>
>> Capitalizing both letters looks important. Certainly this should be
>> a bug...
>>
>> Yasuaki Honda
>> Japan
>>
>> On 2001.12.20, at 10:22, Dan Stanger wrote:
>>
>>>  f(x):=for u in x do print(u); give the following error message:
>>> Incorrect syntax: in is an unknown keyword in a DO statement.
>>>
>>> This works correctly in previous versions.
>>> Dan Stanger
>>>
>>> _______________________________________________
>>> Maxima mailing list
>>> Maxima@www.math.utexas.edu
>>> http://www.math.utexas.edu/mailman/listinfo/maxima
>>>
>>
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>
> --
>
> [ Vadim V. Zhytnikov  <vvzhy@mail.ru>  <vvzhy@td.lpi.ac.ru> ]
>
>
>
>
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