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frenchy64/automatic.clj

Created February 16, 2017 19:20
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Automatic annotations for `for`
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automatic.clj
(defn- multi-perm
"Handles the case when you want the permutations of a list with duplicate items."
[l]
(let [f (frequencies l),
v (vec (distinct l)),
indices (apply concat
(for ^{::t/ann (t/Coll Long)} [^{::t/ann Long} i (range (count v))]
(repeat (f (v i)) i)))]
(map (partial map v) (lex-permutations indices))))
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