Special handling for cases that can map to identity and Base.FixN?

[oschulz]

I often work with code that can optimize/specialize operations for constructs like identity, Base.Fix1 and Base.Fix2. @haberdashPI would you be open to a PR that adds special handling for @lf(_), @lf(obj, _) and @lf(_, obj)?

[haberdashPI]

Sure!