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<h2>Full example</h2>
<pre><code>// Source: https://github.com/antlr/grammars-v4/blob/master/json/JSON.g4
/** Taken from "The Definitive ANTLR 4 Reference" by Terence Parr */
// Derived from http://json.org
grammar JSON;
json
: value
;
obj
: '{' pair (',' pair)* '}'
| '{' '}'
;
pair
: STRING ':' value
;
array
: '[' value (',' value)* ']'
| '[' ']'
;
value
: STRING
| NUMBER
| obj
| array
| 'true'
| 'false'
| 'null'
;
STRING
: '"' (ESC | SAFECODEPOINT)* '"'
;
fragment ESC
: '\\' (["\\/bfnrt] | UNICODE)
;
fragment UNICODE
: 'u' HEX HEX HEX HEX
;
fragment HEX
: [0-9a-fA-F]
;
fragment SAFECODEPOINT
: ~ ["\\\u0000-\u001F]
;
NUMBER
: '-'? INT ('.' [0-9] +)? EXP?
;
fragment INT
: '0' | [1-9] [0-9]*
;
// no leading zeros
fragment EXP
: [Ee] [+\-]? INT
;
// \- since - means "range" inside [...]
WS
: [ \t\n\r] + -> skip
;</code></pre>
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