[racket] Dynamically Bind Functions

Is this the general practice? It looks rather cumbersome and difficult to
plan for.

Is there anything that would prevent me from having to wrap functions in
make-parameter calls? Something like Clojure's binding special form (if
you're familiar with it).

- Cristian
On Dec 21, 2012 6:45 PM, "David Van Horn" <dvanhorn at ccs.neu.edu> wrote:

> On 12/21/12 9:41 PM, Cristian Esquivias wrote:
>
>> I'm trying to replace a function with another using parameterize.
>>
>> For example, when I try:
>>
>> (define (add2 n)
>>    (add1 (add1 n)))
>>
>> (parameterize ([add1 (λ [n] (+ n 2))])
>>    (add2 2))
>>
>> I get an error:
>>
>>   parameterize: contract violation
>>    expected: parameter?
>>    received: #<procedure:add1>
>>
>> How do I re-bind functions in Racket?
>>
>
> You can only use parameterize with names bound to parameter values. Here's
> an example:
>
> #lang racket
> (define padd1 (make-parameter add1))
>
> ((padd1) 4)
>
> (parameterize ([padd1 (λ (n) (+ 2 n))])
>   ((padd1) 4))
>
> David
>
>
>
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