I have a file like this:
declare
a = aexpress
b = bexpress
begin
My scheme program sets the current input port to this file then calls
(declarations (read))
What im getting back, is #f
.
or rather the console says "The object #f is not applicable."
I have been开发者_StackOverflow中文版 over my parenthesis use and cant find any reason it should be returning a boolean value, but I'm sure I'm missing something.
What I want, is ((a aexpress) (b bexpress))
(define declarations
(lambda (token)
(cond (((eq? token 'begin) '())
(else (let* ((name token)
(eqsign (read))
(value (read)))
(cons (list name value) (declarations (read)))))))))
Called by:
(define convert
(lambda (filename)
(begin
(set-current-input-port! (open-input-file filename))
(statement (read))
)
)
)
(define statement (lambda (token) (
cond (
( (eq? token 'declare) (declarations (read)) )
; ( (eq? token 'declare) (declare_statement) )
; ( (eq? token 'begin) (begin_statement) )
; ( (eq? token 'for) (for_statement) )
; ( (eq? token 'if) (if_statement) )
; ( (eq? token 'set) (set_statement) )
; (else (expression_token))
))))
I've fixed the code formatting for you, which reveals what the problem is: you have too many layers of brackets around the (eq? token 'begin)
. The fixed version would look like this:
(define declarations
(lambda (token)
(cond ((eq? token 'begin) '())
(else (let* ((name token)
(eqsign (read))
(value (read)))
(cons (list name value) (declarations (read))))))))
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