given modifier for singleton enum cases

[bishabosha]

Instead of

enumTag[T]:caseIntTagextendsTag[Int] caseStringTagextendsTag[String] objectTag:givenTag[Int] =IntTaggivenTag[String] =StringTag

allow

enumTag[T]:casegivenIntTagextendsTag[Int] casegivenStringTagextendsTag[String]

[LPTK]

That seems useful, but I'd rather spell it given case than case given.

[bishabosha]

That seems useful, but I'd rather spell it given case than case given.

I think that would probably be best - I put it that way because it looked similar to the pattern match syntax