Sources of invalidations

[pabloferz]

I was analyzing sources of invalidations (maybe you are already familiar with it, but some context can be found here and here) and it seems that one of the most important is caused by this definition:

Int(::Infinity) = ∞

which is understandable given how it breaks a lot of the assumptions from inference in Base, where Int(n) isa Int, but now it can also be ::Infinity.

I can see how eliminating that line would make supporting the whole array interface really cumbersome, but maybe it is worth trying to see if it can be restructured to improve precompilation and loading times.

[dlfivefifty]

Really I should do a PR into Base to make this hack unnecessary: I don't remember the offending code but there really isn't a good reason to convert to Int in the first place

[timholy]

All of our indexing is done with Int, so there's a pretty strong argument that size should return an Int.

[dlfivefifty]

It doesn't for BigInt(1):10 so that would be a breaking change to require that