<HTML>Hi! <BLOCKQUOTE TYPE=CITE style="BORDER-LEFT: #0000ff 2px solid; MARGIN-LEFT: 5px; MARGIN-RIGHT: 0px; PADDING-LEFT: 5px">> The full example is rather long, but complains: >   compile: bad syntax; function application is not allowed, because no #%app > syntax transformer is bound in: ... After giving it some thought, I don't have any good guesses.</BLOCKQUOTE> I have managed to fix my macro, but also to formulate a far more consise example of this problem (given below). In the following example, if I "inline" the helper in my macro, everything behaves correctly. But in the case below, I get the following error when my macro is used within a module: a.ss:8:5: compile: bad syntax; function application is not allowed, because no #%app syntax transformer is bound in: (cons 1 2) As before, when this macro is used in the REPL in DrScheme, the macro "works". In this case, the macro is expanded, and the result is evaluated to (1 . 2) as one would expect. The trick to fixing my complte define-struct/prop macro was to move the "helper" code into the body of my syntax case macro. In principle, I could, sort of, understand that there is a problem with referencing a binding of cons in an instantiation of mzscheme in a different phase, and feeding this syntax object back to the value-time environment of module c. But why does it "work" in the REPL, if that is the case? Jim --------------------------- ; c.ss (module c mzscheme     (require "b.ss")     (my-cons 1 2)) --------------------------- ; b.ss (module b mzscheme     (provide my-cons)     (require-for-syntax "a.ss")     (define-syntax (my-cons stx)     (syntax-case stx ()       ((_ a b)        (helper #`a #`b))))) --------------------------- ; a.ss (module a mzscheme     (provide helper)     (define (helper first rest)     #`(cons #,first #,rest))) </HTML>