Xtext grammar for JSON documents

Json.xtext

grammar org.json.Json with org.eclipse.xtext.common.Terminals

generate json "http://www.json.org/"

Object:
	'{' ((members+=Member) (',' members+=Member)*)? '}';

Member:
	key=STRING ':' value=Value;
	
Value:
	Object | STRING | Array | Boolean | Null | Number;

Array:
	'[' ((values+=Value) (',' values+=Value)*)? ']';

Boolean:
  'true' | 'false';

Null:
  'null';

terminal Number:
	'-'? INT? ('.' INT (('E'|'e') '-'? INT)?)?;

{ , "name": "value" } would be valid JSON using this grammar '{' ((members+=Member) (',' members+=Member)*)? '}'; would be a correct rule. The same goes for the Array rule

Indeed. +1 at @pschichtel 's comment.

a number does not need a .

'-'? INT? ('.' INT (('E'|'e') '-'? INT)?)?;

@pschichtel, @stbischof updated the Gist, thanks!