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parcera

Build Status Clojars Project CljDoc

Grammar-based Clojure(script) parser.

Parcera can safely read any Clojure file without any code evaluation.

Parcera uses the wonderful Antlr4 as its parsing engine and focuses on the grammar definition instead.

If you are interested in the grammar definition check Clojure.g4.

setup

Add [org.antlr/antlr4-runtime "4.7.1"] to your dependencies in addition to parcera. This is to avoid adding an unnecessary dependency for the JavaScript users.

All necessary files are delivered with parcera. However, currently only Browser support has been tested.

Check out babashka's pod for parcera. Made by @borkdude

usage

(ns example.core
  (:require [parcera.core :as parcera]))

;;parse clojure code from a string
(parcera/ast (str '(ns parcera.core
                     (:require [clojure.data :as data]
                               [clojure.string :as str]))))

;; => returns a data structure with the result from the parser
(:code
 (:list
  (:symbol "ns")
  (:whitespace " ")
  (:symbol "parcera.core")
  (:whitespace " ")
  (:list
   (:keyword ":require")
   (:whitespace " ")
   (:vector (:symbol "clojure.data") (:whitespace " ") (:keyword ":as") (:whitespace " ") (:symbol "data"))
   (:whitespace " ")
   (:vector (:symbol "clojure.string") (:whitespace " ") (:keyword ":as") (:whitespace " ") (:symbol "str")))))
   
;; get meta data from the parsed code
(meta (second (parcera/ast (str :hello))))
#:parcera.core{:start {:row 1, :column 0}, :end {:row 1, :column 6}}

;; convert an AST back into a string
(parcera/code [:symbol "ns"])
;; "ns"

contributing