clojure-koans/03_lists.clj

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; "Lists can be expressed by function or a quoted form"
(= '(__ __ __ __ __) (list 1 2 3 4 5))
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; "They are Clojure seqs (sequences), so they allow access to the first"
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(= __ (first '(1 2 3 4 5)))
; "As well as the rest"
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(= __ (rest '(1 2 3 4 5)))
; "Count your blessings"
(= __ (count '(dracula dooku chocula)))
; "Before they are gone"
(= __ (count '()))
; "The rest, when nothing is left, is empty"
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(= __ (rest '(100)))
; "Construction by adding an element to the front is easy"
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(= __ (cons :a '(:b :c :d :e)))
; "Conjoining an element to a list isn't hard either"
(= __ (conj '(:a :b :c :d) :e))
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; "You can use a list like a stack to get the first element"
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(= __ (peek '(:a :b :c :d :e)))
; "Or the others"
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(= __ (pop '(:a :b :c :d :e)))
; "But watch out if you try to pop nothing"
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(= __ (try
(pop '())
(catch IllegalStateException e
"No dice!")))
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; "The rest of nothing isn't so strict"
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(= __ (try
(rest '())
(catch IllegalStateException e
"No dice!")))