I can't publish a question because it's not up to the quality standard of the site
Why is it so bad? How can I improve it?
Here it is
I am trying to count words in a large file using the machinery from Iota (https://github.com/thebusby/iota#readme) just for an exercise.
I rewrote the frequencies function, that is based on reduce, to use reducers/fold
Here it is
(defn my-frequencies
"Returns a map from distinct items in coll to the number of times
they appear."
{:static true}
([] {nil 0}) ;;the case with no arguments
([coll] ;; the usual case
(persistent!
(fold
(fn [counts x]
(assoc! counts x (inc (get counts x 0))))
(transient {}) coll)))
)
And then I have the usual passages:
(def mem-file (iota/vec "/home/me/my-file.txt"))
(defn words [line]
(re-seq #"[a-z]+" line))
(def no-blank-lines (iota-filter identity mem-file))
(def seq-of-words (iota-mapcat words no-blank-lines))
here iota-filter is just an alias for clojure.core.reducers/filter and the same goes for iota-mapcat, it´s just an alias for clojure.core.reducers/mapcat
And now the last passage is
(defn freq-map [a-seq-of-words]
(my-frequencies a-seq-of-words))
Now, when, at the REPL prompt I call freq-map, here´s what happens
withiota.core> (freq-map seq-of-words)
ArityException Wrong number of args (0) passed to: core$my-frequencies$fn clojure.lang.AFn.throwArity (AFn.java:437)
withiota.core>
But of course if I call my-frequencies with no arguments:
withiota.core> (my-frequencies)
{nil 0}
withiota.core>
What's going on?
This Clojure reducers library - folding with max could be a relate dquestion but the case with my-frequencies called with 0 arguments is being taken care of, so I guess that question does not apply here
Thanks for any hint
