whenOrNull<TResult extends Object?> method Null safety

  1. @optionalTypeArgs
TResult? whenOrNull<TResult extends Object?>(
  1. {TResult? start(
      )?,
    1. TResult? center(
        )?}
      )
      @optionalTypeArgs, inherited

      Implementation

      @optionalTypeArgs
TResult? whenOrNull<TResult extends Object?>({
  TResult? Function()? start,
  TResult? Function()? center,
}) =>
    throw _privateConstructorUsedError;