Move TypeScript generics as deeply into function signatures as possible

[Avaq]

What about making fold

export function coalesce <LA, RB>(lmapper: (left: LA) => RB): <RA>(rmapper: (right: RA) => RB) => <LB>(source: FutureInstance<LA, RA>) => FutureInstance<never, RB>

I suppose that should be because some throw, like in the case of

See #331. In order to call promise on a Future, the rejection branch must now be compatible with type Error, and thrown exceptions are now merged with the rejection branch, instead of being rethrown.

but not sure if that's a problem of fold

Also in general add the generic <T> as late as possible has proven to be more effective, with the fluture@12.0.0-beta.3 i needed to type way more functions, specially fold and bimap. when i change bimap to

export function bimap<LA, LB>(lmapper: (reason: LA) => LB): <RA, RB>(rmapper: (value: RA) => RB) => (source: FutureInstance<LA, RA>) => FutureInstance<LB, RB>

ts infers way better the bimap type.

Originally posted by @edgarjrg in #370 (comment)