Edamame

EDN parser with location metadata and pluggable dispatch table.

Rationale

This library can be useful when:

You want to include locations in feedback about EDN files.
You want to parse Clojure-like expressions and want to add support for unsupported EDN characters.

This library came out of sci, a small Clojure interpreter.

Features

Parse EDN values with location as metadata.
Pluggable dispatch table to extend EDN.

This library works with:

Clojure on the JVM
ClojureScript

Usage

(require '[edamame.core :refer [parse-string]])

Locations are attached as metadata:

(def s "
[{:a 1}
 {:b 2}]")
(map meta (parse-string s))
;;=>
({:row 2, :col 2}
 {:row 3, :col 2})

(->> "{:a {:b {:c [a b c]}}}"
     parse-string
     (tree-seq coll? #(if (map? %) (vals %) %))
     (map meta))
;;=>
({:row 1, :col 1}
 {:row 1, :col 5}
 {:row 1, :col 9}
 {:row 1, :col 13}
 {:row 1, :col 14}
 {:row 1, :col 16}
 {:row 1, :col 18})

Dispatch on a character, even if it's unsupported in EDN:

(parse-string "@foo" {:dispatch {\@ (fn [val] (list 'deref val))}})
;;=> (deref foo)

Dispatch on dispatch characters:

(parse-string "#\"foo\"" {:dispatch {\# {\" #(re-pattern %)}}})
;;=> #"foo"

(parse-string "#(inc 1 2 %)" {:dispatch {\# {\( (fn [expr] (read-string (str "#" expr)))}}})
;;=> (fn* [p1__11574#] (inc 1 2 p1__11574#))

Test

script/test/jvm
script/test/node
script/test/all

Status

Experimental. Breaking changes are expected to happen at this phase.

Installation

Use as a dependency:

Credits

The code is largely inspired by rewrite-clj and derived projects.

License

Distributed under the Eclipse Public License 1.0. This project contains code from Clojure and ClojureScript which are also licensed under the EPL 1.0. See LICENSE.

ikitommi/edamame