Macros as function chain

So I'm working on a macro, with a builder pattern. and I'd really like to be able to erite something like.


Is this a thing? Does it already exist in some way?

It is not something that currently exists. And I think that there has been at least one RFC trying to define how this might work.

However, if I remember correctly from the text a.b!(...) would have (initially) been just short hand for b!(a, ...)

Oddly, I'm actually not after the macro operating on "a" at all. I just want it to work in that place, and be replaced by a function.

Thankyou though, I think you have helped me solve my current problem.