xforms/README.md
Christophe Grand ac2c5b00b3 typo
2015-09-03 13:00:46 +02:00

1.1 KiB

xforms

More transducers and reducing functions for Clojure!

Usage

Add this dependency to your project:

[net.cgrand/xforms "0.1.0-SNAPSHOT"]
=> (require '[net.cgrand.xforms :as x])

str and str! are two reducing functions to build Strings and StringBuilders in linear time.

=> (quick-bench (reduce str (range 256)))
             Execution time mean : 58,714946 µs
=> (quick-bench (reduce x/str (range 256)))
             Execution time mean : 11,609631 µs

by-key and reduce are two new transducers. Here is an example usage:

;; reimplementing group-by
(defn my-group-by [kfn coll]
  (into {} (x/by-key kfn (x/reduce conj)) coll))

;; let's go transient!
(defn my-group-by [kfn coll]
  (into {} (x/by-key kfn (x/reduce (completing conj! persistent!))) coll))

=> (quick-bench (group-by odd? (range 256)))
             Execution time mean : 29,356531 µs
=> (quick-bench (my-group-by odd? (range 256)))
             Execution time mean : 20,604297 µs

License

Copyright © 2015 Christophe Grand

Distributed under the Eclipse Public License either version 1.0 or (at your option) any later version.