Implicit Function Types

[Blaisorblade]

@Ichoran

If you use an implicit-argument function as a return value, you can consider it either of two ways:

1. It is a formalism that expresses your intent to require an implicit argument, or
2. It is an actual object that is created that evaluates when an implicit argument is available

If the latter, then I worry about the performance hit; this is definitely not a zero-cost abstraction if you’re adding the creation of an ImplicitFunction object to every method call.

Martin just addressed this comment in
https://github.com/lampepfl/dotty/pull/1775/commits/9d57d81096de12f69cbcd8f4113243cc041cd520 (and fixups thereof), making my comment outdated. If this is the approach, I’d like the same optimization to apply to closure-returning methods though.