Super!!! ... thanks a ton Jens.
Now I'll go over the docs to understand why it works :)
Regards,
Kashyap
On Thu, Sep 22, 2016 at 8:52 AM, Jens Axel Søgaard
wrote:
> Here is a bit more.
>
> #lang racket
>
> (require (for-syntax syntax/parse racket/syntax)
> syntax/parse/define)
>
> (defi
Here is a bit more.
#lang racket
(require (for-syntax syntax/parse racket/syntax)
syntax/parse/define)
(define-simple-macro (define-primitive-application-syntax
(primitive-name:id arg:id ...))
(define-simple-macro (primitive-name arg-expr:expr (... ...))
(list 'primitive-name arg-
Thanks Jens ...
I think I'm almost thereI get this "primitive-name: pattern variable
cannot be used outside of a template in: primitive-name" at the very end
now
(require syntax/parse/define)
(define-simple-macro (define-primitive-application-syntax
(primitive-name:id arg:id ...))
(defi
Remove the ().
The construct syntax-case needs the () which in general can be a list of
identifiers,
but most often an empty list, (), is used. Any identifiers in the list are
treated
by syntax-case as a literal.
The construct syntax-parse does not use a list of identifiers. It uses an
alternativ
Thanks Andrew ... I got past that error. I now get an error below -
" syntax-parse: expected clause in: ()"
(define-syntax (define-primitive stx)
(syntax-parse stx () ; ERROR
[(_ (primitive-name:id arg:id ...) body ...+)
#:with table-name
(format-id #'primitive-name "~a-prop
The '...' that is causing the error is a '...' at the level of the
_initial/outer_ macro (define-primitive-application-syntax), and so your final
use of '...' is trying to splice a parameter of the _initial macro_
(define-primitive-application-syntax), but you are actually trying to output a
_l
Thank you so much Jack,
This certainly helps! I was following the tutorial
http://www.greghendershott.com/fear-of-macros/ - It turns out that it too
recommends syntax-parse at the very end :)
When I tried this, I got "syntax: no pattern variables before ellipsis in
template in: ..."
(require syn
Your `syntax-rules` macro-defined macro uses the name "b", but that name is
already bound by the `syntax-case` step of `define-primitive`. So your
expansion looks like this:
(define-primitive (add a b c d) (print (+ a b c d)))
=>
(begin
(define add-property-table (make-hash))
(hash-set! ad
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