operate on tuples

[KiaraGrouwstra]

Array-like type operations are now clunky because we can't operate on tuples until microsoft/TypeScript#5453.
When resolved, ditch much of the array module? Length could just use ['length'], for one.
Currently tuple module is better with tuples (known length) but essentially neither approach is perfect.

[KiaraGrouwstra]

Closing as unactionable until we can do more about this.

[goodmind]

microsoft/TypeScript#24897

[goodmind]

@tycho01

[KiaraGrouwstra]

goodmind Thanks for linking me! It looks like we're still a while off for this though -- I responded there to lay out some of the gaps.

[KiaraGrouwstra]

I guess Concat handles spread in tuple literal types. looks like @fightingcat solved most of the tuple use-cases too!
most interesting use-cases probably need that, so it's unfortunate it's so hacky (tricking the compiler into not seeing the recursion) it may well break.

I guess most of the cool stuff remains blocked on 6606, so I wonder what's unblocked now. path benefits maybe?