import 'package:angel3_combinator/angel3_combinator.dart'; import 'package:string_scanner/string_scanner.dart'; import 'package:test/test.dart'; void main() {} /* void main() { var number = match( RegExp(r'-?[0-9]+(\.[0-9]+)?')) .map((r) => num.parse(r.span.text)); var term = reference(); var r = Recursion(); r.prefix = [number]; r.infix.addAll({ match('*'): (l, r, _) => l * r, match('/'): (l, r, _) => l / r, match('+'): (l, r, _) => l + r, match('-'): (l, r, _) => l - r, match('-'): (l, r, _) => l - r, match('+'): (l, r, _) => l + r, match('/'): (l, r, _) => l / r, match('*'): (l, r, _) => l * r, }); term.parser = r.precedence(0); num parse(String text) { var scanner = SpanScanner(text); var result = term.parse(scanner); print(result.span.highlight()); return result.value; } test('prefix', () { expect(parse('24'), 24); }); test('infix', () { expect(parse('12/6'), 2); expect(parse('24+23'), 47); expect(parse('24-23'), 1); expect(parse('4*3'), 12); }); test('precedence', () { expect(parse('2+3*5*2'), 15); //expect(parse('2+3+5-2*2'), 15); }); } */