On Jun 29, 2015, at 5:56 AM, Alexey Cherkaev <alexey.cherk...@gmail.com> wrote:
> For example, I was thinking of defining syntax to access my implementation of
> multidimensional arrays
> as
>
> (define-syntax aref
> (syntax-rules (set!)
> [(set! (aref ?a ?i ...) ?v) (array-set! ?a ?i ... ?v)]
> [(aref ?a ?i ...) (array-ref ?a ?i ...)]))
>
> but obviously it won't work now as `set!` expects the `id` not an expression
> (`syntax-id-rules` won't work either as `aref` is not an `id`).
#lang racket
(require srfi/17 math/array)
(define (aref a . is)
(array-ref a (list->vector is)))
(set! (setter aref)
(λ (a . is+v)
(match-define (list is ... v) is+v)
(array-set! a (list->vector is) v)))
(define a (mutable-array #[#[1 2] #[3 4]]))
(aref a 0 1)
(set! (aref a 0 1) 20)
(aref a 0 1)
If you wanted, you could also define your own version of set! that does what
you want, which (I think) you would need to do if you needed aref to be a macro.
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