Re: Macro for creating ‘hooks’?

[Hlaaftana]

For some reason the "parameter constraints" section of what was once in the Nim 
manual was moved to the experimental features manual along with term rewriting 
macros, even though it is an independent feature from them. 
[Here](https://nim-lang.org/docs/manual_experimental.html#term-rewriting-macros-parameter-constraints)
 is the documentation in question