parseRefArg function

int? parseRefArg(
  1. String arg
)

Parses an fdb describe ref (@N, N >= 1) into N.

Writes ERROR: Invalid ref: <arg>. Expected @N where N >= 1 to stderr and returns null when arg is malformed.

Implementation

int? parseRefArg(String arg) {
  final ref = arg.startsWith('@') ? int.tryParse(arg.substring(1)) : null;
  if (ref == null || ref < 1) {
    stderr.writeln('ERROR: Invalid ref: $arg. Expected @N where N >= 1');
    return null;
  }
  return ref;
}