Re: [racket] PLAI An inauspicious start

You didn't define the datatype. Shriram On Mon, Sep 13, 2010 at 7:12 AM, wooks . wrote: > Trying out the first example in the book > > #lang plai > (define (parse sexp) >   (cond >     [(number? sexp) (num sexp)] >     [(list? sexp) > (case (first sexp) >    [(+) (add (parse (second sex

[racket] PLAI An inauspicious start

Trying out the first example in the book #lang plai (define (parse sexp) (cond [(number? sexp) (num sexp)] [(list? sexp) (case (first sexp) [(+) (add (parse (second sexp)) (parse (third sexp)))] [(-) (sub (parse (second sexp)) (parse