Re: [Jscheme-user] macro question

[Geoffrey K. <ge...@kn...>]

That's exactly what I was aiming for, thanks!  --Geoffrey

On Friday, Aug 8, 2003, at 09:29 US/Eastern, Ken Anderson wrote:

> You can take this one step further by writing a function producing 
> function:
>
>> (define (picker x)
>     (lambda () (vector-ref x (.nextInt random-gen (vector-length x)))))
> (lambda picker (x)...)
>> (define rocks #(1 2 3 4 5))
> #(1 2 3 4 5)
>> (define rock (picker rocks))
> (lambda picker~0 ()...)
>> (rock)
> 3
>> (rock)
> 2
>
> At 06:35 AM 8/8/2003 -0400, Geoffrey Knauth wrote:
>> Never mind, I guess that was a silly question.  For now I've done 
>> this:
>>
>> (define (pick-one v)
>>  (vector-ref v (.nextInt random-gen (vector-length v))))
>>
>> On Friday, Aug 8, 2003, at 00:00 US/Eastern, Geoffrey Knauth wrote:
>>
>>> Let's say I have:
>>>
>>> (define (stone-size)
>>>  (vector-ref stone-sizes
>>>              (.nextInt random-gen (vector-length stone-sizes))))
>>> (define (stone-thickness)
>>>  (vector-ref stone-thicknesses
>>>              (.nextInt random-gen (vector-length 
>>> stone-thicknesses))))
>>> (define (caulking-type)
>>>  (vector-ref caulking-types
>>>              (.nextInt random-gen (vector-length caulking-types))))
>>>
>>> Notice the repetition?  How can I use a JScheme macro to write this 
>>> once?  Ignore the fact that "es" pluralizes "thickness" while "s" 
>>> pluralizes "size" and "type."
>>>
>>> Thanks,
>>> Geoffrey