peg2 0.1.28 
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PEG+ (Parsing expression grammar) parser source code generator, command line tool.
// Generated by 'peg2'
// https://pub.dev/packages/peg2
void main() {
final parser = ExampleParser();
final result = parser.parse(_text);
if (parser.error != null) {
throw parser.error;
}
print(result);
}
final _text = '''
{"rocket": "🚀 flies to the stars"}
''';
class ExampleParser {
static const _eof = 0x110000;
FormatException error;
int _c;
int _error;
List<String> _expected;
int _failure;
List<int> _input;
List<List<_Memo>> _memos;
var _mresult;
int _pos;
bool _predicate;
dynamic _result;
bool _success;
String _text;
dynamic parse(String text) {
if (text == null) {
throw ArgumentError.notNull('text');
}
_text = text;
_input = _toRunes(text);
_reset();
final result = _parseJson(false, true);
_buildError();
_expected = null;
_input = null;
return result;
}
void _buildError() {
if (_success) {
error = null;
return;
}
String escape(int c) {
switch (c) {
case 10:
return r'\n';
case 13:
return r'\r';
case 09:
return r'\t';
case _eof:
return 'end of file';
}
return String.fromCharCode(c);
}
String getc(int position) {
if (position < _text.length) {
return "'${escape(_input[position])}'";
}
return 'end of file';
}
String report(String message, String source, int start) {
if (start < 0 || start > source.length) {
start = null;
}
final sb = StringBuffer();
sb.write(message);
var line = 0;
var col = 0;
var lineStart = 0;
var started = false;
if (start != null) {
for (var i = 0; i < source.length; i++) {
final c = source.codeUnitAt(i);
if (!started) {
started = true;
lineStart = i;
line++;
col = 1;
} else {
col++;
}
if (c == 10) {
started = false;
}
if (start == i) {
break;
}
}
}
if (start == null) {
sb.writeln('.');
} else if (line == 0 || start == source.length) {
sb.write(' (at offset ');
sb.write(start);
sb.writeln('):');
} else {
sb.write(' (at line ');
sb.write(line);
sb.write(', column ');
sb.write(col);
sb.writeln('):');
}
List<int> escape(int c) {
switch (c) {
case 9:
return [92, 116];
case 10:
return [92, 110];
case 13:
return [92, 114];
default:
return [c];
}
}
const max = 70;
if (start != null) {
final c1 = <int>[];
final c2 = <int>[];
final half = max ~/ 2;
var cr = false;
for (var i = start; i >= lineStart && c1.length < half; i--) {
if (i == source.length) {
c2.insert(0, 94);
} else {
final c = source.codeUnitAt(i);
final escaped = escape(c);
c1.insertAll(0, escaped);
if (c == 10) {
cr = true;
}
final r = i == start ? 94 : 32;
for (var k = 0; k < escaped.length; k++) {
c2.insert(0, r);
}
}
}
for (var i = start + 1;
i < source.length && c1.length < max && !cr;
i++) {
final c = source.codeUnitAt(i);
final escaped = escape(c);
c1.addAll(escaped);
if (c == 10) {
break;
}
}
final text1 = String.fromCharCodes(c1);
final text2 = String.fromCharCodes(c2);
sb.writeln(text1);
sb.writeln(text2);
}
return sb.toString();
}
final temp = _expected.toList();
temp.sort((e1, e2) => e1.compareTo(e2));
final expected = temp.toSet();
final hasMalformed = false;
if (expected.isNotEmpty) {
if (!hasMalformed) {
final sb = StringBuffer();
sb.write('Expected ');
sb.write(expected.join(', '));
sb.write(' but found ');
sb.write(getc(_error));
final title = sb.toString();
final message = report(title, _text, _error);
error = FormatException(message);
} else {
final reason = _error == _text.length ? 'Unterminated' : 'Malformed';
final sb = StringBuffer();
sb.write(reason);
sb.write(' ');
sb.write(expected.join(', '));
final title = sb.toString();
final message = report(title, _text, _error);
error = FormatException(message);
}
} else {
final sb = StringBuffer();
sb.write('Unexpected character ');
sb.write(getc(_error));
final title = sb.toString();
final message = report(title, _text, _error);
error = FormatException(message);
}
}
void _fail(List<String> expected) {
if (_error < _failure) {
_error = _failure;
_expected = [];
}
if (_error == _failure) {
_expected.addAll(expected);
}
}
int _matchChar(int c) {
int result;
if (c == _c) {
_success = true;
_c = _input[_pos += _c <= 0xffff ? 1 : 2];
result = c;
} else {
_success = false;
_failure = _pos;
}
return result;
}
int _matchRanges(List<int> ranges) {
int result;
_success = false;
for (var i = 0; i < ranges.length; i += 2) {
if (ranges[i] <= _c) {
if (ranges[i + 1] >= _c) {
result = _c;
_c = _input[_pos += _c <= 0xffff ? 1 : 2];
_success = true;
break;
}
} else {
break;
}
}
if (!_success) {
_failure = _pos;
}
return result;
}
String _matchString(String text) {
String result;
final length = text.length;
final rest = _text.length - _pos;
final count = length > rest ? rest : length;
var pos = _pos;
var i = 0;
for (; i < count; i++, pos++) {
if (text.codeUnitAt(i) != _text.codeUnitAt(pos)) {
break;
}
}
if (_success = i == length) {
_c = _input[_pos += length];
result = text;
} else {
_failure = _pos + i;
}
return result;
}
bool _memoized(int id) {
final memos = _memos[_pos];
if (memos != null) {
for (var i = 0; i < memos.length; i++) {
final memo = memos[i];
if (memo.id == id) {
_pos = memo.pos;
_mresult = memo.result;
_success = memo.success;
_c = _input[_pos];
return true;
}
}
}
return false;
}
void _memoize(int id, int pos, result) {
var memos = _memos[pos];
if (memos == null) {
memos = [];
_memos[pos] = memos;
}
final memo = _Memo(
id: id,
pos: _pos,
result: result,
success: _success,
);
memos.add(memo);
}
void _reset() {
_c = _input[0];
_error = 0;
_expected = [];
_failure = -1;
_memos = [];
_memos.length = _input.length + 1;
_pos = 0;
_predicate = false;
_success = false;
}
List<int> _toRunes(String source) {
final length = source.length;
final result = List<int>(length + 1);
for (var pos = 0; pos < length;) {
int c;
final start = pos;
final leading = source.codeUnitAt(pos++);
if ((leading & 0xFC00) == 0xD800 && pos < length) {
final trailing = source.codeUnitAt(pos);
if ((trailing & 0xFC00) == 0xDC00) {
c = 0x10000 + ((leading & 0x3FF) << 10) + (trailing & 0x3FF);
pos++;
} else {
c = leading;
}
} else {
c = leading;
}
result[start] = c;
}
result[length] = 0x110000;
return result;
}
dynamic _parseJson(bool $0, bool $1) {
dynamic $2;
final $3 = _pos;
final $4 = _c;
dynamic $6;
_parse_leading_spaces(false, false);
final $11 = _parseValue(true, $1);
if (_success) {
_parse_end_of_file(false, false);
if (_success) {
$6 = $11;
}
}
if (!_success) {
_c = $4;
_pos = $3;
}
$2 = $6;
if (!_success && _error == $3) {
_fail(const [
'\'false\'',
'\'null\'',
'\'true\'',
'\'number\'',
'\'string\'',
'\'[\'',
'\'{\''
]);
}
return $2;
}
dynamic _parseValue(bool $0, bool $1) {
dynamic $2;
final $3 = _pos;
if ($0 && _memoized(6)) {
return _mresult as dynamic;
}
final $5 = _pos;
for (;;) {
List $6;
final $9 = _parseArray(false, $1);
if (_success) {
$6 = $9;
$2 = $6;
break;
}
dynamic $10;
final $13 = _parse_false(false, $1);
if (_success) {
$10 = $13;
$2 = $10;
break;
}
dynamic $14;
final $17 = _parse_null(false, $1);
if (_success) {
$14 = $17;
$2 = $14;
break;
}
dynamic $18;
final $21 = _parse_true(false, $1);
if (_success) {
$18 = $21;
$2 = $18;
break;
}
Map<String, dynamic> $22;
final $25 = _parseObject(false, $1);
if (_success) {
$22 = $25;
$2 = $22;
break;
}
num $26;
final $29 = _parse_number(false, $1);
if (_success) {
$26 = $29;
$2 = $26;
break;
}
String $30;
final $33 = _parse_string(true, $1);
if (_success) {
$30 = $33;
$2 = $30;
break;
}
break;
}
if (!_success && _error == $5) {
_fail(const [
'\'false\'',
'\'null\'',
'\'true\'',
'\'number\'',
'\'string\'',
'\'[\'',
'\'{\''
]);
}
if ($0) {
_memoize(6, $3, $2);
}
return $2;
}
List _parseArray(bool $0, bool $1) {
List $2;
final $3 = _pos;
final $4 = _c;
List $6;
_parse_$LeftSquareBracket(false, false);
if (_success) {
final $10 = _parseValues(false, $1);
final $11 = $10;
_parse_$RightSquareBracket(false, false);
if (_success) {
final v = $11;
List $$;
$$ = v ?? [];
$6 = $$;
}
if (!_success) {
_c = $4;
_pos = $3;
}
}
$2 = $6;
if (!_success && _error == $3) {
_fail(const ['\'[\'']);
}
return $2;
}
List _parseValues(bool $0, bool $1) {
List $2;
final $3 = _pos;
List $6;
final $9 = _parseValue(true, $1);
if (_success) {
List $10;
if ($1) {
$10 = [];
}
for (;;) {
dynamic $11;
final $12 = _pos;
final $13 = _c;
dynamic $15;
_parse_$Comma(true, false);
if (_success) {
final $19 = _parseValue(false, $1);
if (_success) {
$15 = $19;
} else {
_c = $13;
_pos = $12;
}
}
$11 = $15;
if (!_success && _error == $12) {
_fail(const ['\',\'']);
}
if (!_success) {
_success = true;
break;
}
if ($1) {
$10.add($11);
}
}
final v = $9;
final n = $10;
List $$;
$$ = [v, ...n];
$6 = $$;
}
$2 = $6;
if (!_success && _error == $3) {
_fail(const [
'\'false\'',
'\'null\'',
'\'true\'',
'\'number\'',
'\'string\'',
'\'[\'',
'\'{\''
]);
}
return $2;
}
Map<String, dynamic> _parseObject(bool $0, bool $1) {
Map<String, dynamic> $2;
final $3 = _pos;
final $4 = _c;
Map<String, dynamic> $6;
_parse_$LeftBrace(false, false);
if (_success) {
final $10 = _parseMembers(false, $1);
final $11 = $10;
_parse_$RightBrace(false, false);
if (_success) {
final m = $11;
Map<String, dynamic> $$;
$$ = <String, dynamic>{}..addEntries(m ?? []);
$6 = $$;
}
if (!_success) {
_c = $4;
_pos = $3;
}
}
$2 = $6;
if (!_success && _error == $3) {
_fail(const ['\'{\'']);
}
return $2;
}
List<MapEntry<String, dynamic>> _parseMembers(bool $0, bool $1) {
List<MapEntry<String, dynamic>> $2;
final $3 = _pos;
List<MapEntry<String, dynamic>> $6;
final $9 = _parseMember(false, $1);
if (_success) {
List<MapEntry<String, dynamic>> $10;
if ($1) {
$10 = [];
}
for (;;) {
MapEntry<String, dynamic> $11;
final $12 = _pos;
final $13 = _c;
MapEntry<String, dynamic> $15;
_parse_$Comma(true, false);
if (_success) {
final $19 = _parseMember(false, $1);
if (_success) {
$15 = $19;
} else {
_c = $13;
_pos = $12;
}
}
$11 = $15;
if (!_success && _error == $12) {
_fail(const ['\',\'']);
}
if (!_success) {
_success = true;
break;
}
if ($1) {
$10.add($11);
}
}
final m = $9;
final n = $10;
List<MapEntry<String, dynamic>> $$;
$$ = [m, ...n];
$6 = $$;
}
$2 = $6;
if (!_success && _error == $3) {
_fail(const ['\'string\'']);
}
return $2;
}
MapEntry<String, dynamic> _parseMember(bool $0, bool $1) {
MapEntry<String, dynamic> $2;
final $3 = _pos;
final $4 = _c;
MapEntry<String, dynamic> $6;
final $9 = _parse_string(true, $1);
if (_success) {
_parse_$Colon(false, false);
if (_success) {
final $11 = _parseValue(true, $1);
if (_success) {
final k = $9;
final v = $11;
MapEntry<String, dynamic> $$;
$$ = MapEntry(k, v);
$6 = $$;
}
}
if (!_success) {
_c = $4;
_pos = $3;
}
}
$2 = $6;
if (!_success && _error == $3) {
_fail(const ['\'string\'']);
}
return $2;
}
dynamic _parse_end_of_file(bool $0, bool $1) {
dynamic $2;
final $3 = _pos;
final $4 = _c;
dynamic $7;
final $12 = _error;
final $13 = _expected;
final $14 = _failure;
final $15 = $1;
$1 = false;
if (_c >= 0 && _c <= 1114111) {
_success = true;
_c = _input[_pos += _c <= 65535 ? 1 : 2];
} else {
_success = false;
_failure = _pos;
}
_success = !_success;
_c = $4;
_pos = $3;
_error = $12;
_expected = $13;
_failure = $14;
$1 = $15;
var $17;
if (_success) {
$7 = $17;
}
$2 = $7;
if (!_success && _error <= _failure) {
_fail(const ['\'end of file\'']);
}
return $2;
}
dynamic _parse_false(bool $0, bool $1) {
dynamic $2;
dynamic $7;
_matchString('false');
if (_success) {
_parse$$spacing(false, false);
dynamic $$;
$$ = false;
$7 = $$;
}
$2 = $7;
if (!_success && _error <= _failure) {
_fail(const ['\'false\'']);
}
return $2;
}
List<int> _parse_leading_spaces(bool $0, bool $1) {
List<int> $2;
$2 = _parse$$spacing(false, false);
if (!_success && _error <= _failure) {
_fail(const ['\'leading spaces\'']);
}
return $2;
}
dynamic _parse_null(bool $0, bool $1) {
dynamic $2;
dynamic $7;
_matchString('null');
if (_success) {
_parse$$spacing(false, false);
dynamic $$;
$$ = null;
$7 = $$;
}
$2 = $7;
if (!_success && _error <= _failure) {
_fail(const ['\'null\'']);
}
return $2;
}
dynamic _parse_true(bool $0, bool $1) {
dynamic $2;
dynamic $7;
_matchString('true');
if (_success) {
_parse$$spacing(false, false);
dynamic $$;
$$ = true;
$7 = $$;
}
$2 = $7;
if (!_success && _error <= _failure) {
_fail(const ['\'true\'']);
}
return $2;
}
String _parse_string(bool $0, bool $1) {
String $2;
final $3 = _pos;
if ($0 && _memoized(73)) {
return _mresult as String;
}
final $4 = _c;
final $5 = _pos;
String $7;
_matchString('\"');
if (_success) {
List<int> $11;
if ($1) {
$11 = [];
}
for (;;) {
final $12 = _parse$$char(false, $1);
if (!_success) {
_success = true;
break;
}
if ($1) {
$11.add($12);
}
}
_matchString('\"');
if (_success) {
_parse$$spacing(false, false);
final c = $11;
String $$;
$$ = String.fromCharCodes(c);
$7 = $$;
}
if (!_success) {
_c = $4;
_pos = $5;
}
}
$2 = $7;
if (!_success && _error <= _failure) {
_fail(const ['\'string\'']);
}
if ($0) {
_memoize(73, $3, $2);
}
return $2;
}
num _parse_number(bool $0, bool $1) {
num $2;
final $3 = _pos;
num $7;
String $10;
final $12 = $1;
$1 = false;
final $14 = _pos;
final $15 = _c;
_matchChar(45);
var $27 = _pos;
for (;;) {
_matchChar(48);
if ($27 < _failure) {
$27 = _failure;
}
if (_success) {
break;
}
const $35 = [49, 57];
_matchRanges($35);
if (_success) {
for (;;) {
const $38 = [48, 57];
_matchRanges($38);
if (!_success) {
_success = true;
break;
}
}
}
if ($27 < _failure) {
$27 = _failure;
}
if (_success) {
break;
}
_c = $15;
_pos = $14;
_failure = $27;
break;
}
if (_success) {
final $41 = _pos;
final $42 = _c;
_matchChar(46);
if (_success) {
var $50 = false;
for (;;) {
const $51 = [48, 57];
_matchRanges($51);
if (!_success) {
_success = $50;
break;
}
$50 = true;
}
if (!_success) {
_c = $42;
_pos = $41;
}
}
final $55 = _pos;
final $56 = _c;
const $62 = [69, 69, 101, 101];
_matchRanges($62);
if (_success) {
const $64 = [43, 43, 45, 45];
_matchRanges($64);
var $68 = false;
for (;;) {
const $69 = [48, 57];
_matchRanges($69);
if (!_success) {
_success = $68;
break;
}
$68 = true;
}
if (!_success) {
_c = $56;
_pos = $55;
}
}
_success = true;
}
if (_success) {
$10 = _text.substring($3, _pos);
}
$1 = $12;
if (_success) {
_parse$$spacing(false, false);
final n = $10;
num $$;
$$ = num.parse(n);
$7 = $$;
}
$2 = $7;
if (!_success && _error <= _failure) {
_fail(const ['\'number\'']);
}
return $2;
}
String _parse_$LeftBrace(bool $0, bool $1) {
String $2;
String $7;
final $10 = _matchString('{');
if (_success) {
_parse$$spacing(false, false);
$7 = $10;
}
$2 = $7;
if (!_success && _error <= _failure) {
_fail(const ['\'{\'']);
}
return $2;
}
String _parse_$RightBrace(bool $0, bool $1) {
String $2;
String $7;
final $10 = _matchString('}');
if (_success) {
_parse$$spacing(false, false);
$7 = $10;
}
$2 = $7;
if (!_success && _error <= _failure) {
_fail(const ['\'}\'']);
}
return $2;
}
String _parse_$LeftSquareBracket(bool $0, bool $1) {
String $2;
String $7;
final $10 = _matchString('[');
if (_success) {
_parse$$spacing(false, false);
$7 = $10;
}
$2 = $7;
if (!_success && _error <= _failure) {
_fail(const ['\'[\'']);
}
return $2;
}
String _parse_$RightSquareBracket(bool $0, bool $1) {
String $2;
String $7;
final $10 = _matchString(']');
if (_success) {
_parse$$spacing(false, false);
$7 = $10;
}
$2 = $7;
if (!_success && _error <= _failure) {
_fail(const ['\']\'']);
}
return $2;
}
String _parse_$Comma(bool $0, bool $1) {
String $2;
final $3 = _pos;
if ($0 && _memoized(125)) {
return _mresult as String;
}
String $7;
final $10 = _matchString(',');
if (_success) {
_parse$$spacing(false, false);
$7 = $10;
}
$2 = $7;
if (!_success && _error <= _failure) {
_fail(const ['\',\'']);
}
if ($0) {
_memoize(125, $3, $2);
}
return $2;
}
String _parse_$Colon(bool $0, bool $1) {
String $2;
String $7;
final $10 = _matchString(':');
if (_success) {
_parse$$spacing(false, false);
$7 = $10;
}
$2 = $7;
if (!_success && _error <= _failure) {
_fail(const ['\':\'']);
}
return $2;
}
int _parse$$char(bool $0, bool $1) {
int $2;
final $3 = _pos;
final $4 = _c;
for (;;) {
int $6;
final $7 = _c;
final $8 = _pos;
_matchChar(92);
if (_success) {
final $10 = _parse$$escaped(false, $1);
if (_success) {
$6 = $10;
} else {
_c = $7;
_pos = $8;
}
}
if (_success) {
$2 = $6;
break;
}
_c = $4;
_pos = $3;
int $11;
final $14 = _parse$$unescaped(false, $1);
if (_success) {
$11 = $14;
$2 = $11;
break;
}
break;
}
return $2;
}
int _parse$$escaped(bool $0, bool $1) {
int $2;
final $3 = _pos;
final $4 = _c;
for (;;) {
int $6;
final $9 = _matchChar(34);
if (_success) {
$6 = $9;
$2 = $6;
break;
}
int $10;
final $13 = _matchChar(92);
if (_success) {
$10 = $13;
$2 = $10;
break;
}
int $14;
final $17 = _matchChar(47);
if (_success) {
$14 = $17;
$2 = $14;
break;
}
int $18;
_matchChar(98);
if (_success) {
int $$;
$$ = 0x8;
$18 = $$;
}
if (_success) {
$2 = $18;
break;
}
int $22;
_matchChar(102);
if (_success) {
int $$;
$$ = 0xC;
$22 = $$;
}
if (_success) {
$2 = $22;
break;
}
int $26;
_matchChar(110);
if (_success) {
int $$;
$$ = 0xA;
$26 = $$;
}
if (_success) {
$2 = $26;
break;
}
int $30;
_matchChar(114);
if (_success) {
int $$;
$$ = 0xD;
$30 = $$;
}
if (_success) {
$2 = $30;
break;
}
int $34;
_matchChar(116);
if (_success) {
int $$;
$$ = 0x9;
$34 = $$;
}
if (_success) {
$2 = $34;
break;
}
int $38;
final $39 = _c;
final $40 = _pos;
_matchChar(117);
if (_success) {
final $42 = _parse$$hexdig4(false, $1);
if (_success) {
$38 = $42;
} else {
_c = $39;
_pos = $40;
}
}
if (_success) {
$2 = $38;
break;
}
_c = $4;
_pos = $3;
break;
}
return $2;
}
int _parse$$hexdig4(bool $0, bool $1) {
int $2;
final $3 = _pos;
final $4 = _c;
int $6;
final $9 = _parse$$hexdig(false, $1);
if (_success) {
final $10 = _parse$$hexdig(false, $1);
if (_success) {
final $11 = _parse$$hexdig(false, $1);
if (_success) {
final $12 = _parse$$hexdig(false, $1);
if (_success) {
final a = $9;
final b = $10;
final c = $11;
final d = $12;
int $$;
$$ = a * 0xfff + b * 0xff + c * 0xf + d;
$6 = $$;
}
}
}
if (!_success) {
_c = $4;
_pos = $3;
}
}
$2 = $6;
return $2;
}
int _parse$$hexdig(bool $0, bool $1) {
int $2;
for (;;) {
int $6;
const $9 = [97, 102];
_matchRanges($9);
if (_success) {
int $$;
$$ = $$ - 97;
$6 = $$;
}
if (_success) {
$2 = $6;
break;
}
int $11;
const $14 = [65, 70];
_matchRanges($14);
if (_success) {
int $$;
$$ = $$ - 65;
$11 = $$;
}
if (_success) {
$2 = $11;
break;
}
int $16;
const $19 = [48, 57];
_matchRanges($19);
if (_success) {
int $$;
$$ = $$ - 48;
$16 = $$;
}
if (_success) {
$2 = $16;
break;
}
break;
}
return $2;
}
int _parse$$unescaped(bool $0, bool $1) {
int $2;
for (;;) {
int $6;
const $9 = [32, 33];
final $10 = _matchRanges($9);
if (_success) {
$6 = $10;
$2 = $6;
break;
}
int $11;
const $14 = [35, 91];
final $15 = _matchRanges($14);
if (_success) {
$11 = $15;
$2 = $11;
break;
}
int $16;
const $19 = [93, 1114111];
final $20 = _matchRanges($19);
if (_success) {
$16 = $20;
$2 = $16;
break;
}
break;
}
return $2;
}
List<int> _parse$$spacing(bool $0, bool $1) {
List<int> $2;
for (;;) {
const $10 = [9, 10, 13, 13, 32, 32];
_matchRanges($10);
if (!_success) {
_success = true;
break;
}
}
return $2;
}
}
class _Memo {
final int id;
final int pos;
final result;
final bool success;
_Memo({
this.id,
this.pos,
this.result,
this.success,
});
}
// ignore_for_file: unused_element
// ignore_for_file: unused_fieldMetadata
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unverified uploader
Metadata
PEG+ (Parsing expression grammar) parser source code generator, command line tool.
Repository (GitHub)
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License
unknown (LICENSE)
Dependencies
args, dart_style, enumerable, lists, meta, path, strings
