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  1. ;; Define helper functions
  2. (define (drop-while pred lis)
  3.   (if (or (null? lis) (not (pred (car lis))))
  4.       lis
  5.       (drop-while pred (cdr lis))))
  6.  
  7. (define (take-while pred lis)
  8.   (define (take-while-helper pred lis result)
  9.     (if (and (not (null? lis)) (pred (car lis)))
  10.         (take-while-helper pred (cdr lis) (cons (car lis) result))
  11.         (reverse result)))
  12.   (take-while-helper pred lis '()))
  13.  
  14. (define (char-other? ch)
  15.   (not (or (= (char->integer ch) 91)
  16.            (= (char->integer ch) 93)
  17.            (= (char->integer ch) 40)
  18.            (= (char->integer ch) 41)
  19.            (= (char->integer ch) 32)
  20.            (= (char->integer ch) 10))))
  21.  
  22. (define (process-other chars)
  23.   (and (not (null? chars))
  24.        (let* ((token-chars (take-while char-other? chars))
  25.               (rest (drop-while char-other? chars)))
  26.          (list token-chars rest))))
  27.  
  28. ;; Custom function to check if all elements in a list are characters
  29. (define (all-char? lis)
  30.   (if (null? lis)
  31.       #t
  32.       (and (char? (car lis)) (all-char? (cdr lis)))))
  33.  
  34. ;; Function to tag tokens with their type
  35. (define (tag-token type value)
  36.   (list type value))
  37.  
  38. ;; Functions for Dot Count
  39. (define (process-dots chars)
  40.   (let* ((dot-chars (take-while (lambda (ch) (char=? ch (integer->char 46))) chars))  ; char 46 is '.'
  41.          (num-dots (length dot-chars))
  42.          (rest (drop-while (lambda (ch) (char=? ch (integer->char 46))) chars)))
  43.     (list num-dots rest)))
  44.  
  45. ;; Define main tokenize function with integrated new functions
  46. (define (tokenize input)
  47.   (let loop ((chars (string->list input)) (tokens '()))
  48.     (cond
  49.       ((null? chars) (reverse tokens))  ; Return the reversed tokens
  50.       ((char=? (car chars) (integer->char 91))  ; Handle opening bracket [
  51.        (loop (cdr chars) (cons (tag-token 'open-bracket "[") tokens)))
  52.       ((char=? (car chars) (integer->char 93))  ; Handle closing bracket ]
  53.        (loop (cdr chars) (cons (tag-token 'close-bracket "]") tokens)))
  54.       ((char=? (car chars) (integer->char 40))  ; Handle opening parenthesis
  55.        (loop (cdr chars) (cons (tag-token 'open-parenthesis "(") tokens)))
  56.       ((char=? (car chars) (integer->char 41))  ; Handle closing parenthesis
  57.        (loop (cdr chars) (cons (tag-token 'close-parenthesis ")") tokens)))
  58.       ((char=? (car chars) (integer->char 32))  ; Skip spaces
  59.        (loop (cdr chars) tokens))
  60.       ((char=? (car chars) (integer->char 46))  ; Handle dots (.)
  61.        (let* ((result (process-dots chars))
  62.               (num-dots (car result))
  63.               (rest (cadr result)))
  64.          (loop rest (cons (tag-token 'dots num-dots) tokens))))  ; Use a tagged list structure
  65.       (else
  66.        (let* ((result (process-other chars))
  67.               (token (car result))
  68.               (rest (cadr result)))
  69.          (loop rest (cons (tag-token 'other token) tokens)))))))  ; End of tokenize function
  70.  
  71. ;; Example usage
  72. (define input "(define) f g (). 1 2")
  73.  
  74. ;; Tokenize the input
  75. (let ((tokens (tokenize input)))
  76.   (write tokens)  ; Write the intermediate tokenized output for debugging
  77.   (newline)
  78.   tokens)  ; Return the intermediate tokenized output
  79.  
  80.  
Success #stdin #stdout 0.01s 8056KB
comments (?)
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Standard input is empty
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((open-parenthesis "(") (other (#\d #\e #\f #\i #\n #\e)) (close-parenthesis ")") (other (#\f)) (other (#\g)) (open-parenthesis "(") (close-parenthesis ")") (dots 1) (other (#\1)) (other (#\2)))
https://ideone.com/fs7IrG
language:
Scheme (chicken 4.13)
created:
7 days ago
visibility:
public

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