json5_grammar.txt

main : json5-text;

json5-text: json5-value;

json5-value: (
    json5-null |
    json5-boolean |
    json5-string |
    json5-number |
    json5-object |
    json5-array
);

json5-null: 'null';
json5-boolean: ('true' | 'false');

json5-array: (
    '[' ']' |
    '[' json5-element-list ','? ']'
);

json5-object: (
    '{' '}' |
    '{' json5-member-list ','? '}'
);

json5-member-list: (
    json5-member |
    json5-member-list ',' json5-member
);

json5-member: json5-member-name ':' json5-value;

json5-member-name: (json5-identifier | json5-string);

json5-element-list: (
    json5-value |
    json5-element-list ',' json5-value
);

json5-identifier: 'a';


# Number handling
# ---------------

json5-number: (
    json5-numeric-literal |
    '+' json5-numeric-literal |
    '-' json5-numeric-literal
);

json5-numeric-literal: (
    numeric-literal |
    'Infinity' |
    'NaN'
);

numeric-literal: (
    decimal-literal |
    hex-integer-literal
);

decimal-literal: (
    decimal-integer-literal '.' decimal-digits? exponent-part? |
    '.' decimal-digits exponent-part? |
    decimal-integer-literal exponent-part?
);

decimal-integer-literal: (
    '0' |
    non-zero-digit decimal-digits?
);

decimal-digits: (
    decimal-digit |
    decimal-digits decimal-digit
);

decimal-digit: '[0-9]';

non-zero-digit: '[1-9]';

exponent-part: exponent-indicator signed-integer;

exponent-indicator: 'e' | 'E';

signed-integer: (
    decimal-digits |
    '+' decimal-digits |
    '-' decimal-digits
);

hex-integer-literal: (
    '0x' hex-digit |
    '0X' hex-digit |
    hex-integer-literal hex-digit
);

hex-digit: (
    '[0-9]' |
    '[a-f]' |
    '[A-F]'
);

# String Handling
# ---------------

json5-string: (
    '"' json5-double-string-characters? '"' |
    '\'' json5-single-string-characters? '\''
);

json5-double-string-characters: json5-double-string-character json5-double-string-characters?;
json5-single-string-characters: json5-single-string-character json5-single-string-characters?;

json5-double-string-character: (
    '[^"\\\r\n]' |
    '\' escape-sequence |
    line-continuation |
    '\x{2028}' |
    '\x{2029}'
);

json5-double-string-character: (
    '[^\'\\\r\n]' |
    '\' escape-sequence |
    line-continuation |
    '\x{2028}' |
    '\x{2029}'
);

escape-sequence: (
    character-escape-sequence |
    '0' | # [lookahead decimal-digit?]
    hex-escape-sequence |
    unicode-escape-sequence
);

character-escape-sequence: (
    single-escape-character |
    non-escape-character
);

single-escape-character: '[\'"\\bfnrtv]';
non-escape-character: 'a';

line-continuation: 'a';