intOption function

int intOption(String longName, String? shortName, String argument, int defaultValue,)

Tests whether the argument has the longName or the shortName and an integer. Returns the value of the int argument or the defaultValue Throws OptionException on error. longName: the long name to inspect, e.g. 'max-length' shortName: the short name to inspect, e.g. 'm' argument: argument to inspect, e.g. '--max-length=3' defaultValue: if the arguments does not match: this value is returned

Implementation

int intOption(
    String longName, String? shortName, String argument, int defaultValue) {
  var rc = defaultValue;
  if (argument == '--$longName') {
    throw OptionException('missing "<int>" in $argument');
  } else if (argument.startsWith('--$longName=')) {
    var matcher = RegExp(r'=(\d+)$').firstMatch(argument);
    if (matcher == null) {
      throw OptionException('missing <int> in $argument');
    }
    rc = int.parse(matcher.group(1)!);
  } else if (shortName != null && argument.startsWith('-$shortName')) {
    var matcher = RegExp('^-$shortName(\\d+)\$').firstMatch(argument);
    if (matcher == null) {
      throw OptionException('missing <int> in $argument');
    }
    rc = int.parse(matcher.group(1)!);
  }
  return rc;
}