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36.9 Stack iteration thunks

Iteration thunks are procedures accepting no arguments and returning an item from a collection; when the iteration finishes: the return value is the void object. Iteration thunks can be used with the facilities of the library (vicare containers iteration-thunks) (see iteration thunks). The following syntactic bindings are exported by the library (vicare containers stacks).

Function: make-stack-iteration-thunk stack

Build and return a new iteration thunk popping the objects from stack.

(import (vicare)
  (vicare containers stacks)
  (vicare containers iteration-thunks))

(define (xcons a b)
  (cons b a))

(iteration-thunk-fold
    xcons
  '()
  (make-stack-iteration-thunks (stack)))
⇒ ()

(iteration-thunk-fold
    xcons
  '()
  (make-stack-iteration-thunks (stack 0 1 2 3 4 5)))
⇒ (5 4 3 2 1 0)