Add a .SwitchAsync method which behaves as .Match returning a Task

[adnang]

I've seen too many times developers using .Switch instead of .Match when calling async void code inside the lambdas, because the default behaviour when you want to perform a void operation is to .Switch rather than .Match, resulting in

OneOf<T1, T2> res = GetResult();

res.Switch(async t1 => await ProcessT1(t1), async t2 => await ProcessT2(t2));

which isn't awaited correctly (resulting in exceptions being lost)

A .SwitchAsync method which accepts a Func<T, Task> for each parameter would make it really clear than an async option can be used (even gives an IDE hint), and the behaviour would be the same as .Match(Func<T, Task>)

[mcintyre321]

Interesting... ware your thoughts on overloading on Switch (without the Async suffix) i.e.

public void Switch(Action<T0> f0, Action<T1> f1) { ... }
public Task Switch(Func<T0, Task> f0, Func<T1, Task> f1) { ... }

[adnang]

because the non-async overload is the original and the default for most current usages, i would make the Async part explicit. Omitting async is cleaner when the async version is the default, but omitting it here could still result in the same issue with developers forgetting to await the resulting task