Racket has two versions of syntax-local-binding, one that does lookup of syntax parameters and one that don't. So it would be interesting to know why. Anyway with this mail, there is a patch that enable syntax-local-value to lookup syntax-parameters as well. Also let's fix the test. With the definitions as in the previous mail use in stead, (define-syntax info (lambda (x) (syntax-case x () ((_ f) (let-values (((key ret) (syntax-local-binding #'f))) (datum->syntax x (eq? ret %f))))))) and (info f) => #t (fluid-let-syntax ((f (lambda x #'#t))) (info f)) => #f