anchor.diff:          expect(
             builder.build(),
             equals({
  -            'parent': {'key1': 1, 'key2': 2}
  +            'parent': {
  +              'key1': 1,
  +              'child': {'key2': 2}
  +            }
             }),
           );
         });
  +      test(
  +        'marks previously implicitly created tables that are defined by '
  +        'dotted key/value pairs as explicitly defined',
  +        () {
  +          var builder = TomlMapBuilder();
  +          builder.visitStandardTable(TomlStandardTable(TomlKey([
  +            TomlUnquotedKey('parent'),
  +            TomlUnquotedKey('table'),
  +            TomlUnquotedKey('child'),
  +          ])));
  +          builder.visitStandardTable(
  +              TomlStandardTable(TomlKey([TomlUnquotedKey('parent')])));
  +          builder.visitKeyValuePair(TomlKeyValuePair(
  +            TomlKey([
  +              TomlUnquotedKey('table'),
  +              TomlUnquotedKey('key'),
  +            ]),
  +            TomlLiteralString('value'),
  +          ));
  +          expect(
  +            () => builder.visitStandardTable(
  +              TomlStandardTable(TomlKey([
  +                TomlUnquotedKey('parent'),
  +                TomlUnquotedKey('table'),
  +              ])),
  +            ),
  +            throwsA(equals(TomlRedefinitionException(
  +              TomlKey([TomlUnquotedKey('parent'), TomlUnquotedKey('table')]),
  +            ))),
  +          );
  +        },
  +      );
         test('cannot open inline table', () {
           var builder = TomlMapBuilder();
           builder.visitKeyValuePair(TomlKeyValuePair(
  
positive.code:           ),
          );
        });
        test('can create sub-tables within tables defined via dotted keys', () {
          var builder = TomlMapBuilder();
          builder.visitKeyValuePair(TomlKeyValuePair(
  
negative.code:           TomlInteger.dec(BigInt.from(1)),
          ));
          builder.visitStandardTable(TomlStandardTable(
            TomlKey([TomlUnquotedKey('parent'), TomlUnquotedKey('child')]),
          ));
          builder.visitKeyValuePair(TomlKeyValuePair(
            TomlKey([TomlUnquotedKey('key2')]),
  