So, as a designer of miniature languages and syntactic extensions, specify it!
A well written function must also abide by some promise or specification—contracts on the inputs and invariants on the outputs. I don't see why new syntactic structures are much different from that.
I think there's undue spookiness around macros among lots of programmers, especially those who haven't sought to solve some problem with them.
- "It's too powerful for the common person."
- "It's way too likely to make code confusing."
- "It's invariably too hard to reason about."
- "It won't work on a team because everybody is going to
make their own weird incompatible language and it's just not scalable."
All of these sentiments are complete bunk, and I argue are against common wisdom around other programming abstractions, like functions or classes.
