integer method

int integer(String name, { required int orElse, })

The value parsed as an integer.

A value that is present but unparseable throws rather than falling back to orElse. Someone set it on purpose, and silently ignoring it would leave the app running on a port nobody routed to.

Implementation

int integer(String name, {required int orElse}) {
  final value = this[name];
  if (value == null) {
    return orElse;
  }

  return int.tryParse(value) ??
      (throw StateError(
        'Environment variable "$name" is "$value", which is not an integer.',
      ));
}