2010-02-20 15:30:24 +00:00
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(meditations
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"Lists can be expressed by function or a quoted form"
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2011-02-03 18:00:03 +00:00
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(= '(__ __ __ __ __) (list 1 2 3 4 5))
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2010-02-20 15:30:24 +00:00
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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)))
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"As well as the rest"
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(= __ (rest '(1 2 3 4 5)))
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"The rest when nothing is left is empty"
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(= __ (rest '(100)))
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"And construction by adding an element to the front is simple"
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(= __ (cons :a '(:b :c :d :e)))
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"Conjoining an element to a list can be done in the reverse order"
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(= __ (conj '(:a :b :c :d :e) 0))
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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)))
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"Or the others"
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(= __ (pop '(:a :b :c :d :e)))
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"But watch out if you try to pop nothing"
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(= __ (try
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(pop '())
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(catch IllegalStateException e "No dice!")))
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"The rest of nothing isn't so strict"
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(= __ (try
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(rest '())
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(catch IllegalStateException e "No dice!"))))
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