Any plans on making get public?

[pbackus]

Any plans on making get public?

[pbackus]

No, get will never be public.

If you want something similar, I suggest a tryGet function like the following:

T tryGet(T, ST)(ST st)
    if (isSumType!ST)
{
    return st.tryMatch!((T value) => value);
}

This will throw an exception when the requested type is not found.

[iK4tsu]

Yes, however that doesn't work with betterC. If not get, then maybe a @system version of it. But if it isn't in your plans, which is understandable, then I'll just keep using match.

That being said, I don't think a function to extract the value directly would damage the lib in any way, if it were @system and well documented. It would come down to the user's choice if he wanted to use the function or not.

[pbackus]

Good API design is as much about what you leave out as about what you include. I want sumtype to guide users into the pit of success, and providing a function that crashes at runtime if you use it incorrectly is contrary to that goal.

[iK4tsu]

How about adding a version of tryMatch/tryGet suitable for betterC. This would assert if the requested type wasn't found.

[pbackus]

You can write it yourself if you really want it. I will not include such a function in the sumtype library, for the reason stated above.

[FFY00]

Hold my beer while I fork the standard library for my project... because I want to use something in betterC...?

[iK4tsu]

I don't know if this covers all cases, but based on your example above:

T tryGet(T, ST)(ST st)
	if (isSumType!ST)
{
  	static if (st.Types.length == 1)
      	return st.match!((T value) => value);
  	else
      	return st.match!(
        	(T value) => value,
        	function T (_) { assert(false); }
    	);
}

Not really what I want, but it might do as a workaround.

[pbackus]

Personally I would recommend something like this for BetterC (and in general, honestly):

Nullable!T get(T, ST)(ST st)
    if (isSumType!ST)
{
    return st.match!(
        (value) {
            static if (is(typeof(value) == T))
                return nullable(value);
            else
                return Nullable!T();
        }
    );
}