I have a macro that creates transformer bindings at phases 0 and 1: (define-syntax (f stx) (with-syntax ([name (cadr (syntax-e stx))]) #'(begin (define-syntax name (syntax-id-rules () [_ 1])) (begin-for-syntax (define-syntax name (syntax-id-rules () [_ 2]))))))
Normally, this works fine. I have syntax transformers bound at both phases that can resolve "name" with syntax-local-value. In an expression context, the phase-0 transformer binding can be overridden temporarily with let-syntax: (cons x (let-syntax ([x (syntax-id-rules () [_ 'one])] [y (λ (stx) (datum->syntax stx (syntax-local-value #'x)))]) (list x y))) This produces '(1 one #<set!-transformer>). With syntax-local-eval instead of syntax-local-value, it produces '(1 one 2). Because "f" produces begin-for-syntax, it only works in a module or top-level evaluation context: (let () (f x) x) /tmp/g.rkt:10:8: begin-for-syntax: not in a definition context in: (begin-for-syntax (define-syntax x (syntax-id-rules () (_ 2)))) Is there a way to override temporarily the phase-1 transformer binding as well? Eric -- You received this message because you are subscribed to the Google Groups "Racket Users" group. To unsubscribe from this group and stop receiving emails from it, send an email to racket-users+unsubscr...@googlegroups.com. For more options, visit https://groups.google.com/d/optout.