51 lines
1.1 KiB
Markdown
51 lines
1.1 KiB
Markdown
# xforms
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More transducers and reducing functions for Clojure!
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## Usage
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Add this dependency to your project:
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```clj
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[net.cgrand/xforms "0.1.0-SNAPSHOT"]
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```
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```clj
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=> (require '[net.cgrand.xforms :as x])
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```
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`str` and `str!` are two reducing functions to build Strings and StringBuilders in linear time.
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```clj
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=> (quick-bench (reduce str (range 256)))
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Execution time mean : 58,714946 µs
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=> (quick-bench (reduce x/str (range 256)))
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Execution time mean : 11,609631 µs
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```
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`by-key` and `reduce` are two new transducers. Here is an example usage:
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```clj
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;; reimplementing group-by
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(defn my-group-by [kfn coll]
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(into {} (x/by-key kfn (x/reduce conj)) coll))
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;; let's go transient!
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(defn my-group-by [kfn coll]
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(into {} (x/by-key kfn (x/reduce (completing conj! persistent!))) coll))
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=> (quick-bench (group-by odd? (range 256)))
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Execution time mean : 29,356531 µs
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=> (quick-bench (my-group-by odd? (range 256)))
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Execution time mean : 20,604297 µs
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```
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## License
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Copyright © 2015 Christophe Grand
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Distributed under the Eclipse Public License either version 1.0 or (at
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your option) any later version.
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