Echte und endständige Rekursionen JS

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< Grundlagen der funktionsorientierten Programmierung mit SCHEME

Beispiel:

(define fak-rek
  (lambda (n)
    (print "fak-rek " n)
    (if (= n 0)
        1
        (* n (fak-rek (- n 1))))))

Trace-Modus:

(fak-rek 5)

Beispiel:

(define fak-help
  (lambda (n fak)
    (print "fak-help " n " " fak)
    (if (= n 0)
        fak
        (fak-help (- n 1) (* n fak)))))

(define fak-it
  (lambda (n)
    (print "fak-it " n)
    (fak-help n 1)))

Trace-Modus:

(fak-it 5)

Beispiel:

(define indent 0)
(define fak-rek
  (lambda (n)
    (set! indent (+ indent 1))
    (print (make-string indent #\space) "fak-rek " n)
    (let ([r
      (if (= n 0)
         1
          (* n (fak-rek (- n 1)))
      )])
      (print (make-string indent #\space) r)
      (set! indent (- indent 1))
      r
    )
  )
)

Trace-Modus:

(fak-rek 5)

Beispiel:

(define indent 0)
(define fak-help
  (lambda (n fak)
    (set! indent (+ indent 1))
    (print (make-string indent #\space) "fak-help " n " " fak)
    (let ([r
      (if (= n 0)
        fak
        (fak-help (- n 1) (* n fak)))
      ])
      (print (make-string indent #\space) r)
      (set! indent (- indent 1))
      r
    )
  )
)

(define fak-it
  (lambda (n)
    (set! indent (+ indent 1))
    (print (make-string indent #\space) "fak-it " n)
    (let ([r (fak-help n 1)])
      (print (make-string indent #\space) r)
      (set! indent (- indent 1))
      r
    )
  )
)

Trace-Modus:

(fak-it 5)

Echte und endständige Rekursionen JS

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