Scheme Lexical Analyzer - scheme

Question

Currently working on a lexical analyzer in Scheme. I'm new to scheme but have a general understanding of what to do. I am following a online tutorial, however I keep getting this error because I'm not using UMASS scheme. What can I do to replace this class (Error: record-parse unbound identifier). Below is my code
#lang racket
(define record_parse
(lambda(noun adjective adverb conjunction prep terminator)
((noun) '(dog cat rat house tree))
((adjective) '(furry fast lazy sneaky))
((adverb) '(quickly silently))
((conjunction) '(and or))
((prep) '(with around up))
((terminator) '(!))))
(define noun '(dog cat rat house tree))
(define adjective '(furry fast lazy sneaky))
(define adverb '(quickly silently))
(define conjunction '(and or))
(define prep '(with around up))
(define terminator '(!))
(define class_parse (record-parse 'parse '(full full)))
(define cons_parse (car class_parse))
(define sel_parse (caddr class_parse))
(define tree_parse (car sel_parse))
(define rest_parse (cadr sel_parse))
(define parse_article
(lambda (list_of_tokens)
(cond
((null? list_of_tokens) #f)
((member? (car list_of_tokens) '(a the))
(cons_parse
(car list_of_tokens)
(cdr list_of_tokens)))
(else #f )
)
)
)
(define (member? x list)
(if (null? list) #f
(if (equal? x (car list)) #t
(member? x (cdr list)))))
(define parse_noun
(lambda (list_of_tokens)
(cond
((null? list_of_tokens) #f)
((member? (car list_of_tokens) noun)
(cons_parse
(car list_of_tokens)
(cdr list_of_tokens)))
(else #f )
)
)
)
(define parse_noun_phrase
(lambda (list_of_tokens)
(let ((p_det (parse_article list_of_tokens)))
(if p_det
(let ( (p_n (parse_noun (rest_parse p_det))))
(if p_n
(cons_parse
(list 'noun_phrase
(tree_parse p_det)
(tree_parse p_n))
(rest_parse p_n)
)
#f)
)
#f)
)
))
(define verb '(loves hates eats chases stalks))
(define parse_verb
(lambda (list_of_tokens)
(cond
((null? list_of_tokens) #f)
((member? (car list_of_tokens) verb)
(cons_parse
(car list_of_tokens)
(cdr list_of_tokens)))
(else #f )
)
)
)
(define parse_verb_phrase
(lambda (list_of_tokens)
(let ((p1 (parse_verb list_of_tokens)))
(if p1
(let ((p2 (parse_noun_phrase (rest_parse p1))))
(if p2
(cons_parse
(list 'verb_phrase
(tree_parse p1)
(tree_parse p2))
(rest_parse p2)
)
#f)
)
#f)
)
))
(define parse_sentence
(lambda (list_of_tokens)
(let ((p1 (parse_noun_phrase list_of_tokens)))
(if p1
(let ((p2 (parse_verb_phrase (rest_parse p1))))
(if p2
(cons_parse
(list 'sentence
(tree_parse p1)
(tree_parse p2))
(rest_parse p2)
)
#f)
)
#f)
)
))
;example of parsing a sentence
;(example
; '(parse_sentence '(the dog chases the cat))
; (cons_parse
; '(sentence (noun_phrase the dog)
; (verb_phrase chases
; (noun_phrase the cat)
; (terminator)))
; '()
; )
; )
(begin
(display "Enter a Sentance in (): ")
(let ((input (read)))
(parse_article (parse_sentence input))))
I am getting the error with the (define class_parse (record-parse 'parse '(full full)))

Answer 1

The procedure you defined is called record_parse, but you're trying to invoke it as record-parse. After that typo is fixed, you'll get a different error: record_parse is defined to receive 6 parameters, but you're passing only two: 'parse and '(full full). And the body of record_parse doesn't make sense, it seems that you tried to implement a case expression, but that's not how it's written in Scheme - at all.
That's only for starters, it looks like there are more errors. You should test each procedure individually until you get the hang of the syntax and before writing more complex behavior that involves using all of the procedures.