Idea: Borrowck Transparent Function Calls

[scottmcm]

I think the same thing about this as when essentially the same thing came up 2 days ago

Private lifetime inference

TBH, getting lifetime bounds right is rarely the noisy part. I think it'd be entirely fine to solve that part like we solve -> _: with a structured suggestion inferred from the body. Then I agree with the mention of a macro fn: then it could potentially even just be macro fn find_best(primary, fallback) { if primary.is_valid() { &primary.summary } else { &fallback.summary } } where not only do I not need to put in the lifetimes but I can even leave off the types and have it just happen i…