[Jscheme-user] a little problem with define-macro

[Borislav I. <bor...@ko...>]

Hi,

I tried using define-macro (i.e. the built in macros) to simplify
working with streams thus:

> (define-macro (make-stream h t) (cons h (delay t)))
(macro make-stream (h t)...)

But then:

> (define (enum start end) 
   (if (> start end) '() (make-stream start (enum (+ start 1) end))))

SchemeException: expected object of type list (i.e. pair or empty), but
got: , "
(lambda delay~3 ()...)"
        at jsint.E.error(E.java:14)
        at jsint.E.typeError(E.java:24)
        at jsint.U.toList(U.java:180)
        at jsint.U.listToVector(U.java:772)
        at jsint.Scheme.analyze(Scheme.java:487)
        at jsint.Scheme.analyze(Scheme.java:475)
        at jsint.Scheme.analyze(Scheme.java:490)
        at jsint.Scheme.analyze(Scheme.java:473)
        at jsint.Scheme.analyze(Scheme.java:459)
        at jsint.Scheme.analyze(Scheme.java:490)
        at jsint.Scheme.analyze(Scheme.java:490)
        at jsint.Scheme.analyze(Scheme.java:475)
        at jsint.Scheme.eval(Scheme.java:434)
        at jsint.Scheme.eval(Scheme.java:424)
        at jsint.Scheme.readEvalWriteLoop(Scheme.java:208)
        at jsint.Scheme.runJscheme(Scheme.java:186)
        at jsint.Scheme.defaultMain(Scheme.java:149)
        at jsint.Scheme.main(Scheme.java:124)
        at jscheme.REPL.main(REPL.java:138)


If expand "manually" the macro:

(define (enum start end) 
   (if (> start end) '() (cons start (delay (enum (+ start 1) end)))))

there is no problem. 

BTW, it also works with define-syntax macros..

Best,
Boris