edn-parser-js

EDN parser library for JS/TS.

Rationaly

There are a number of existing EDN parsers for JS/TS. But I'm not aware of one that supports all EDN features that modern Clojure could emit/parse. First of all, it's namespaced maps introduced in Clojure 1.9

This parser is trying to support everything that Clojure could emit and parse using clojure.edn, even if it's not in EDN "spec". It includes namespaced maps, | in symbols/keywords, metadata parsing.

Types mapping

EDN Type	TS Type	EDN Value	JS Value
integer/float	number	123	123
nil	null	nil	null
boolean	boolean	true	true
string	string	"hello"	"hello!"
char	{ char: string }	\a	{ char: "a" }
symbol	{ symbol: string; ns?: string }	foo	{ symbol: "foo" }
		bar/foo	{ symbol: "foo", ns: "bar" }
keyword	{ keyword: string; ns?: string }	:foo	{ keyword: "foo" }
		:bar/foo	{ keyword: "foo", ns: "bar" }
vector	{ list: EDN[] }	[1 2 3]	{ list: [1, 2, 3] }
map	{ map: [EDN, EDN][] }	{"hello" "world}	{ map: [["hello", "world"]]}
set	{ set: EDN[] }	#{1 2 3}	{ set: [1, 2, 3] }
list	{ list: EDN[] }	(1 2 3)	{ list: [1, 2 ,3] }
^meta ...	{ meta: [EDN, EDN][]; value: EDN }	^{"comment": "hi"} []	{ meta: {"comment": "hi"}, value: List()}

Install

npm install edn-parser-js

Usage

import { ednParse } from 'edn-parser-js';

ednParse('{:hello "world"}');
//=> Map(1) { { keyword: 'hello' } => 'world' }

API

export type EDNSymbol = { symbol: string; ns?: string };

export type EDN =
  | number
  | null
  | boolean
  | string
  | EDNSymbol
  | { keyword: string; ns?: string }
  | { char: string }
  | EDN[]
  | { map: [EDN, EDN][] }
  | { set: EDN[] }
  | { list: EDN[] }
  | { tag: EDNSymbol; value: EDN }
  | { meta: [EDN, EDN][]; value: EDN };

ednParse(string): EDN

ednParseMulti(string): EDN[]