I'm doing a bit of macrobatics where I'm creating a series of definitions,
during which I want to also do define-for-syntax for some syntax transformers
that are used in a produced syntax-parameterize form.
In a top level call to this macro, things would be fine. However, I set up some
syntax parameters first with splicing-syntax-parameterize.
Now I get an error of the form
begin-for-syntax: not in a definition context
in: (begin-for-syntax (define-values (foo) foo-def))
context...:
backtrace
This boils down to the fact that
(let () (define-for-syntax (foo x) x) 0)
is not legal, because the internal definition context set up is only for phase
0.
How can I get around this? Is this an intended limitation?
There is more odd behavior to this. Consider the following interaction:
Welcome to Racket v5.3.0.24.
> (let () (define-syntax foo (λ (stx) (syntax-case stx () [(_ e) #'e]))) (foo
> 0))
0
> (let ()
(define-for-syntax foo-def (λ (stx) (syntax-case stx () [(_ e) #'e])))
(define-syntax foo foo-def)
(foo 0))
foo-def: undefined;
cannot reference undefined identifier
context...:
/home/ianj/plt/pltgit/collects/racket/private/misc.rkt:87:7
> (let () (define-for-syntax foo-def (λ (stx) (syntax-case stx () [(_ e)
> #'e]))) 0)
begin-for-syntax: not in a definition context
in: (begin-for-syntax (define-values (foo-def) (λ (stx) (syntax-case stx ()
((_ e) (syntax e))))))
context...:
/home/ianj/plt/pltgit/collects/racket/private/misc.rkt:87:7
If the define-for-syntax is just not allowed, then shouldn't I get an error the
form of the latter instead of the former?
Thanks,
-Ian
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