combine2<T1 extends Object, T2 extends Object> static method

Result<(T1, T2)> combine2<T1 extends Object, T2 extends Object>(Result<T1> r1, Result<T2> r2, [ @noFutures Err<(T1, T2)> onErr(Result<T1>, Result<T2>)? ])

Combines 2 Result outcomes into 1 containing a tuple of their values if all are Ok.

If any are Err, applies onErr function to combine errors.

See also: combineResult.

Implementation

static Result<(T1, T2)> combine2<T1 extends Object, T2 extends Object>(
  Result<T1> r1,
  Result<T2> r2, [
  @noFutures Err<(T1, T2)> Function(Result<T1>, Result<T2>)? onErr,
]) {
  final combined = combineResult<Object>(
    [r1, r2],
    onErr: onErr == null
        ? null
        : (l) => onErr(l[0].transf<T1>(), l[1].transf<T2>()).transfErr(),
  );
  return combined.map((l) => (l[0] as T1, l[1] as T2));
}