Y-combinator in Racket supporting variant arguments

First Post:

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Y-combinator:

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(define Y
  (lambda (g)
    (let ((d (lambda (f)
               (lambda args
                 (apply (g (f f)) args)))))
      (d d))))

An example:

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(let ((fact (Y (lambda (fact)
                 (lambda (n)
                   (if (zero? n)
                       1
                       (* n (fact (- n 1)))))))))
  (fact 10))

Another example:

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(let ((gcd (Y (lambda (gcd)
                (lambda (a b)
                  (if (zero? b)
                      a
                      (gcd b (remainder a b))))))))
  (gcd 12 8))