char function

@useResult Parser<String> char(String value, { String? message, bool ignoreCase = false, bool unicode = false, })

Returns a parser that accepts a specific character value.

• message defines a custom error message.
• If ignoreCase is true, the character is matched in a case-insensitive manner.
• If unicode is true, the character is matched using full unicode character parsing (as opposed to UTF-16 code units).

Implementation

@useResult
Parser<String> char(
  String value, {
  String? message,
  bool ignoreCase = false,
  bool unicode = false,
}) {
  final charCode = toCharCode(value, unicode: unicode);
  final predicate = ignoreCase
      ? optimizedString(value, ignoreCase: ignoreCase, unicode: unicode)
      : SingleCharPredicate(charCode);
  message ??=
      '"${toReadableString(value, unicode: unicode)}"'
      '${ignoreCase ? ' (case-insensitive)' : ''} expected';
  return CharacterParser(predicate, message, unicode: unicode);
}