Possibly I'm going about this wrong. I'm trying to understand how best
to construct maps from sequences, by applying a function which returns a
key / value pair.
Something like this:
(ns test (:use clojure.contrib.str-utils))
(def test-str "foo=1;bar=2;baz=3")
(defn split-kv [text]
(let [[k v] (re-split #"=" text )]
{k v}))
(defn split-pairs [text]
(re-split #";" text))
(map split-kv (split-pairs test-str))
-> ({"foo" "1"} {"bar" "2"} {"baz" "3"})
Doesn't really do what I had in mind. And yeah, I figured out that I can
convert that to a hash-map in various ways, but I had expected map to be
able to do this. So I wrote this:
(defn map-assoc
"Returns a map consisting of f applied to coll, where f is a function
returning a key and value. f can return either a sequence with two
values or a single item map."
[f coll]
(loop [map {}
s (seq coll)]
(if s
(let [item (f (first s))]
(recur (if (associative? item)
(conj map item)
(assoc map (first item) (second item)))
(next s)))
map)))
This seems a little bit more like what I expected:
(map-assoc split-kv (split-pairs test-str))
-> {"baz" "3", "bar" "2", "foo" "1"}
Am I overlooking some already existing function hidden away someplace
that does this?
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