Idiomatic C# - using switch for pattern matching:

[FreeApophis]

I like the idea to do pattern matching with the switch expression instead of our Match function:

louthy/language-ext#838

[bash]

.Case is essentially .ToNullable(), right?

[FreeApophis]

At least for the Option type.
Don't know how much sense it makes to Either, especially becuase of exhaustiveness...
The Sequence use case with Head and Tail is done with tuple pattern matching, we don't have those.

I think I want to see an implementation to see the problems.

[bash]

I'd really like to see something like dotnet/csharplang#1047 implemented 😕…

On a somewhat related note: We could make TryGetValue public. (I know, I know, but it slightly better than Case because it avoids boxing)

[FreeApophis]

I am not very fond of matching true and false, but positional pattern sound great.

            var something = t.TryGetValue(out var value) switch
            {
                true => value,
                false => -1,
            };

[bash]

Well you could use a ternary expression with TryGetValue:

var something = t.TryGetValue(out var value) ? value : -1;

[bash]

Making TryGetValue public also enables the use of Option in situations where you're forced to do things imperatively. (e.g. exception handling)

Option<IExceptionHandler> FindExceptionHandler(Exception exception) => ...;

try
{
    ...
} catch (Exception exception) when (FindExceptionHandler(exception).TryGetValue(out var handler))
{
    handler.HandleException(exception);
}

[FreeApophis]

lang-ext goes the other way, and defines a functional way to Try.

[bash]

As long as it doesn't start polluting the stack trace too much…

[bash]

I've created a new issue for TryGetValue: #296