A few things:
1. You're mixing elements of `syntax-rules` and `syntax-case` /
`syntax-parse`. The former has an implicit template in its right-hand
side, so you don't need the `#``, whereas you do with `syntax-case` /
`syntax-parse`.
2. If you want this to define a function (as I'm guessing from the name
`fun`), you should add parentheses around the name you're defining.
3. Because you're not trying to *match* the name `fun`, but only
expanding to it, you don't need it in the literal list.
Here's a version that should do what you want:
(define-syntax mysyn
(syntax-rules ()
[(mysyn element ...)
(define (fun)
(display element)
...)]))
(mysyn 1 2 3)
Or, using the simpler `define-syntax-rule`:
(define-syntax-rule (mysyn element ...)
(define (fun)
(display element)
...))
Of course, it's usually best to use functions wherever possible, and
only use macros as a last resort. Assuming you're planning to use the
code (i.e., you're not using it to learn about macros), I'd write it
like this:
(define (fun . args) (for-each display args))
Functions compose more easily, and are easier to understand and to debug.
Vincent
On Wed, 30 Mar 2016 15:06:24 -0500,
[email protected] wrote:
>
> Consider a toy macro defined as:
>
> (define-syntax mysyn
> (syntax-rules(fun)
> [(mysyn element ...)
> (begin
> #`(define fun
> (display element)...))]))
>
> and a list:
> (define l '(1 2 3))
>
> Is there a way to call the macro like so: (mysyn l). When I try this, the
> syntax object created looks like: '(define fun (display l)).
> What I want it to look like is:
>
> '(define fun
> (display 1)
> (display 2)
> (display 3))
>
>
> In other words, my question is whether/how I can pass the entire list to the
> macro and let the macro be expanded on each element of it.
>
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