Re: Eval, tail calls, (current-module), and backward compatibility

[Ludovic Courtès]

Andy Wingo <address@hidden> skribis:

> On Wed 18 Jan 2012 23:21, address@hidden (Ludovic Courtès) writes:
>
>> Andy Wingo <address@hidden> skribis:
>>
>>> On Wed 18 Jan 2012 22:18, address@hidden (Ludovic Courtès) writes:
>>>
>>>>         (('apply (f args))
>>>>          (apply (eval f env) (eval args env)))
>>>
>>> This is in primitive-eval (and here, `eval' is locally bound).  Mark is
>>> talking about R5RS `eval' (`scm_eval').
>>
>> OK, but ‘scm_eval’ is not recursive, so no wonder it’s not
>> tail-recursive.  :-)
>>
>> (I’m confident I’m missing something, but I just fail to see what.  ;-))
>
> Hee hee :)  The point is that this should loop indefinitely:
>
>   (define (loop)
>     (eval '(loop) (current-module)))
>   (loop)

OK, got it.

TBH, I’d be happy to document the limitation and live with it,
especially since it’s not a regression.

Thanks,
Ludo’.