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Similar thing, not same

齊藤敦志
・1 min read

Common Lisp has do syntax. And Scheme too.

They have same form, but different semantic.

;; Common Lisp
(do ((i 0 (+ i 1))
     (j '() (cons (lambda()i) j)))
    ((= i 3)
     (mapcar (lambda(x)(funcall x)) j)))
;; → (3 3 3)
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;; Scheme
(do ((i 0 (+ i 1))
     (j '() (cons (lambda()i) j)))
    ((= i 3)
     (map (lambda(x)(x)) j)))
;; → (2 1 0)
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Scheme's do make a new location every time for each loop. Common Lisp is not so.

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