Add constants for legal DragEffect values

[japgolly]

No description provided.

[sjrd]

Could you wrap these docs at 80 characters, please? It's too long to read on mobile.

[sjrd]

That's all.

[japgolly]

No worries, I'll make both changes shortly.

About constant-folding, didn't you say a while back that it only applied to primitives? Is String an exception to that?

[sjrd]

Yes, String is considered a "primitive". As well as classOf[C], IIRC.
Actually it would be more accurate to say literals rather primitives. 10, 5.4d, "hello" and classOf[String] are all literals. But 5.toByte isn't.

[japgolly]

Ahhh that makes a lot of sense. After learning macros somewhat I imagine it's probably Literal(Constant(…)) that are foldable? When you said primitives, I was thinking in the Java sense so no AnyRef subtypes which I thought excluded java.lang.String.

Anyhoo, changes are done. Please take another look.

(Also as requested, I trimmed the comments to line-length 80 but they're now obviously inconsistent with the rest of the file which seems to be around 94. But as you wish. 👐 )

[sjrd]

LGTM