pipeAsync<T2> method
If result
is Err
then returns this Err
as is.
If result
is Ok
then returns result of call await f(result.val)
.
If result of call f() is null - returns Err('function returned null').
If result of call f() is Result
- returns it as is.
If call of f() throws exception, then returns Err
.
Implementation
Future<Result<T2>> pipeAsync<T2>(Future Function(T) f) async {
if (isErr) {
return Err<T2>(err);
}
var argument = unwrap;
var res = await f(argument);
if (res == null) {
return Err<T2>(
StateError('Result of f($argument) == null, where `f` is $f'));
} else {
if (res is Error) {
return Err<T2>(res);
} else {
if (res is Ok) {
return Ok(res.unwrap);
} else if (res is Err) {
return Err<T2>(res.err);
} else {
return Ok(res);
}
}
}
}