[Top][All Lists]
[Date Prev][Date Next][Thread Prev][Thread Next][Date Index][Thread Index]
Re: when and unless
From: |
Ludovic Courtès |
Subject: |
Re: when and unless |
Date: |
Tue, 06 Dec 2011 15:39:49 +0100 |
User-agent: |
Gnus/5.110018 (No Gnus v0.18) Emacs/24.0.90 (gnu/linux) |
Hi,
Andy Wingo <address@hidden> skribis:
> On Thu 30 Jun 2011 12:44, Andy Wingo <address@hidden> writes:
>
>> I think we should add `when' and `unless' to the default environment.
>>
>> They go like this:
>>
>> (define-syntax when
>> (syntax-rules ()
>> ((_ test then then* ...)
>> (if test (begin then then* ... (if #f #f))))))
>>
>> (define-syntax unless
>> (syntax-rules ()
>> ((_ test else else* ...)
>> (if (not test) (begin else else* ... (if #f #f))))))
>
> WDYT? `unless' is nice for assertions, `when' is its converse, and most
> Schemes have them. I would like to add them to Guile too.
Yes, feel free.
Ludo’.
- Re: when and unless, (continued)
- Re: when and unless, Chris K. Jester-Young, 2011/12/06
- Re: when and unless, David Kastrup, 2011/12/07
- Re: when and unless, Chris K. Jester-Young, 2011/12/07
- Re: when and unless, David Kastrup, 2011/12/08
- Re: when and unless, Chris K. Jester-Young, 2011/12/08
- Re: when and unless, David Kastrup, 2011/12/08
- Re: when and unless, Ian Price, 2011/12/08
- Re: when and unless, Chris K. Jester-Young, 2011/12/07
Re: when and unless, Chris K. Jester-Young, 2011/12/06
Re: when and unless,
Ludovic Courtès <=