2014-05-02 21:37:11 +00:00
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(ns koans.03-vectors
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(:require [koan-engine.core :refer :all]))
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2014-01-26 00:04:22 +00:00
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2010-02-06 22:00:08 +00:00
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(meditations
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2013-03-04 23:06:46 +00:00
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"You can use vectors in clojure as array-like structures"
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2010-10-29 15:45:47 +00:00
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(= __ (count [42]))
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2010-02-06 22:00:08 +00:00
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2013-03-04 23:06:46 +00:00
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"You can create a vector from a list"
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2010-09-29 00:18:47 +00:00
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(= __ (vec '(1)))
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2010-02-06 22:00:08 +00:00
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2013-03-04 23:06:46 +00:00
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"Or from some elements"
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(= __ (vector nil nil))
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2010-10-27 05:04:32 +00:00
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2010-07-26 23:20:42 +00:00
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"But you can populate it with any number of elements at once"
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(= [1 __] (vec '(1 2)))
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2010-02-06 22:00:08 +00:00
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2013-03-04 23:10:04 +00:00
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"Conjoining to a vector is different than to a list"
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(= __ (conj [111 222] 333))
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2010-02-06 22:00:08 +00:00
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2010-07-26 23:20:42 +00:00
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"You can get the first element of a vector like so"
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2010-09-29 00:18:47 +00:00
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(= __ (first [:peanut :butter :and :jelly]))
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2010-02-06 22:00:08 +00:00
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2010-07-26 23:20:42 +00:00
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"And the last in a similar fashion"
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(= __ (last [:peanut :butter :and :jelly]))
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"Or any index if you wish"
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(= __ (nth [:peanut :butter :and :jelly] 3))
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"You can also slice a vector"
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2010-11-04 13:01:34 +00:00
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(= __ (subvec [:peanut :butter :and :jelly] 1 3))
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"Equality with collections is in terms of values"
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2011-02-08 21:57:15 +00:00
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(= (list 1 2 3) (vector 1 2 __)))
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