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The capturing of continuations

Scheme provides a primitive that captures a continuation of an expression E in a context C.

The primitive is called call-with-current-continuation, or call/cc as a short alias.

call/cc takes a parameter, which is a function of one parameter.

The parameter of the function is bound to the continuation.


Context C and the capturing

(+ 5 (call/cc (lambda (e) (* 4 3)) ))
(cons 1 (cons 2 (cons 3 (call/cc (lambda (e) '()) ))))
(define x 5)
(if (= 0 x)
    (remainder (* (call/cc (lambda (e) (+ x 1)) ) (- x 1)) x))