Question: How to use with async / await?

Question: is there a way to call Match with async / await? Related to #26

I have:

public async Task<OneOf<Foo, None>> HandleAsync(GetFooQuery query)
{
	var foo = await GetByIdAsync(query.FooId);

	return foo.Match<OneOf<Foo, None>>(
		f => GetCustomerNameForFooAsync(f).Result,
		_ => new None());
}

private async Task<OneOf<Foo, None>> GetByIdAsync(FooId fooId)
{ ...

private async Task<Foo> GetCustomerNameForFooAsync(Foo foo)
{ ...

but the .Result on the end is a bit icky (edit: and is not asyncronous!). Would be nice if I could do something like:

public async Task<OneOf<Foo, None>> HandleAsync(GetFooQuery query)
{
	var foo = await GetByIdAsync(query.FooId);

	return foo.Match<OneOf<Foo, None>>(
		async f => await GetCustomerNameForFooAsync(f),
		_ => new None());
}

[mcintyre321]

Hi Matt

I think the cleanest way to write it with the current lib is if you get liberal with async:

async Task<OneOf<Foo, None>> HandleAsync(GetFooQuery query)
{
	var foo = await GetByIdAsync(query.FooId);

	return await foo.Match<Task<OneOf<Foo, None>>>(
		async f => await GetCustomerNameForFooAsync(f),
		async _ => new None()); //you'll get a warning about it not being async, but ignore it!
}

[mattfrear]

Thanks for the reply Harry.

Yep, that works, it’s the same suggestion you made last time. My bad - I missed your comment //you'll get a warning about it not being async, but ignore it.

I’m pedantic about not having compiler warnings so I stuck with the ugly Task.FromResult and then edited my message to get rid of the question altogether.