[Top][All Lists]
[Date Prev][Date Next][Thread Prev][Thread Next][Date Index][Thread Index]
Re: loop translations (was: Re: language translator help)
From: |
Marius Vollmer |
Subject: |
Re: loop translations (was: Re: language translator help) |
Date: |
28 Apr 2002 20:15:26 +0200 |
User-agent: |
Gnus/5.09 (Gnus v5.9.0) Emacs/21.2 |
"John W. Eaton" <address@hidden> writes:
> On 28-Apr-2002, Marius Vollmer <address@hidden> wrote:
>
> | "John W. Eaton" <address@hidden> writes:
> |
> | Your approach is essentially right. Let me try to formalize it a bit
> | with some macros:
>
> Thanks. With the macros, the loops are much more readable to me, but
> there is still the (apparent, at least to a Scheme novice) complexity
> of call/cc.
Yes, but I think it is properly encapsulated with 'with-exit'.
> | The problem with the macros above is that they are not hygienic,
>
> Sorry, I'm not sure I understand what that means.
They can shadow identifiers from the user. Code like
(let ((continue #t))
(while continue
(set! continue #f)))
wont work since the 'continue' identifier inside the while does not
refer to the one introduced by the let. A good solution would be to
make the continue feature optional and let the user choose the name of
the function. Much like 'with-exit', where the name of the exiting
function is determined by the user, not the macro.
> | avoiding call/cc is not so easy and is hopefully
> | not really necessary. One could generate continuation-passing code
> | and hope that Guile will execute it more efficiently than the
> | occasional call/cc,
>
> What is continuation passing?
Start here:
http://www.scheme.com/tspl2d/further.html#g1849
> It's important to me that looping not be any slower than it already is
> in Octave.
I'd say you should first do the simple thing (using call/cc) and later
worry about performance.
loop translations (was: Re: language translator help), John W. Eaton, 2002/04/27
Re: loop translations (was: Re: language translator help), Marius Vollmer, 2002/04/28
Re: loop translations (was: Re: language translator help), John W. Eaton, 2002/04/28
Re: loop translations (was: Re: language translator help),
Marius Vollmer <=
Re: loop translations (was: Re: language translator help), Marius Vollmer, 2002/04/28
Re: loop translations (was: Re: language translator help), Clinton Ebadi, 2002/04/29
Re: loop translations (was: Re: language translator help), Eric E Moore, 2002/04/29
Re: loop translations (was: Re: language translator help), Eric E Moore, 2002/04/30
Re: loop translations (was: Re: language translator help), Neil Jerram, 2002/04/28
translators and scoping rules (was: Re: language translator help), John W. Eaton, 2002/04/27