dj.peg 0.3.0

A Ring inspired (aka functional and composable) parsing expression grammar (PEG) library.

With leiningen use [org.bmillare/dj.peg "0.3.0"]

A while back I wrote a PEG generator. Since it was buggy, I've completely rewritten it and also tried to write it psuedo literate programming (LP) style, in that I try to make it more of a story. I don't rely on any LP tools, its just heavily commented and should flow linearly. So if you never knew about PEGs before and want to dive into it, this would be a good opportunity to check it out.

A quick example:

(require [dj.peg :as peg])

(let [num (peg/alt (peg/t #"\d+") #(Integer/parseInt %))
      whitespace (peg/t #"\s+")
      triplet (peg/s num whitespace num whitespace num)]
  (peg/parse triplet "3 44 2theremaininginput"))

;;user=> {:result [3 " " 44 " " 2] :unconsumed-input "theremaininginput"}

API summary:

t: token

s: sequence

*: star

+: plus

?: opt

|: choice

!?: not?

&?: and?

alt: alter-result

Author

Brent Millare brent.millare@gmail.com

License

Copyright (c) Brent Millare. All rights reserved. The use and distribution terms for this software are covered by the Eclipse Public License 1.0 (http://opensource.org/licenses/eclipse-1.0.php) which can be found in the file epl-v10.html at the root of this distribution. By using this software in any fashion, you are agreeing to be bound by the terms of this license. You must not remove this notice, or any other, from this software.