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/*
* JSON Grammar
* ============
*
* Based on the grammar from RFC 7159 [1].
*
* Note that JSON is also specified in ECMA-262 [2], ECMA-404 [3], and on the
* JSON website [4] (somewhat informally). The RFC seems the most authoritative
* source, which is confirmed e.g. by [5].
*
* [1] http://tools.ietf.org/html/rfc7159
* [2] http://www.ecma-international.org/publications/standards/Ecma-262.htm
* [3] http://www.ecma-international.org/publications/standards/Ecma-404.htm
* [4] http://json.org/
* [5] https://www.tbray.org/ongoing/When/201x/2014/03/05/RFC7159-JSON
*/
/* ----- 2. JSON Grammar ----- */
JSON_text
= ws value:value ws { return value; }
begin_array = ws "[" ws
begin_object = ws "{" ws
end_array = ws "]" ws
end_object = ws "}" ws
name_separator = ws ":" ws
value_separator = ws "," ws
ws "whitespace" = [ \t\n\r]*
/* ----- 3. Values ----- */
value
= false
/ null
/ true
/ object
/ array
/ number
/ string
false = "false" { return false; }
null = "null" { return null; }
true = "true" { return true; }
/* ----- 4. Objects ----- */
object
= begin_object
members:(
head:member
tail:(value_separator m:member { return m; })*
{
var result = {}, i;
result[head.name] = head.value;
for (i = 0; i < tail.length; i++) {
result[tail[i].name] = tail[i].value;
}
return result;
}
)?
end_object
{ return members !== null ? members: {}; }
member
= name:string name_separator value:value {
return { name: name, value: value };
}
/* ----- 5. Arrays ----- */
array
= begin_array
values:(
head:value
tail:(value_separator v:value { return v; })*
{ return [head].concat(tail); }
)?
end_array
{ return values !== null ? values : []; }
/* ----- 6. Numbers ----- */
number "number"
= minus? int frac? exp? { return parseFloat(text()); }
decimal_point = "."
digit1_9 = [1-9]
e = [eE]
exp = e (minus / plus)? DIGIT+
frac = decimal_point DIGIT+
int = zero / (digit1_9 DIGIT*)
minus = "-"
plus = "+"
zero = "0"
/* ----- 7. Strings ----- */
string "string"
= quotation_mark chars:char* quotation_mark { return chars.join(""); }
char
= unescaped
/ escape
sequence:(
'"'
/ "\\"
/ "/"
/ "b" { return "\b"; }
/ "f" { return "\f"; }
/ "n" { return "\n"; }
/ "r" { return "\r"; }
/ "t" { return "\t"; }
/ "u" digits:$(HEXDIG HEXDIG HEXDIG HEXDIG) {
return String.fromCharCode(parseInt(digits, 16));
}
)
{ return sequence; }
escape = "\\"
quotation_mark = '"'
unescaped = [\x20-\x21\x23-\x5B\x5D-\u10FFFF]
/* ----- Core ABNF Rules ----- */
/* See RFC 4234, Appendix B (http://tools.ietf.org/html/rfc4627). */
DIGIT = [0-9]
HEXDIG = [0-9a-f]i