Re: when and unless

[Ludovic Courtès]

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’.