Well said. Honestly I don't understand this "function coloring argument" at all in zig's context.

Function is the smallest unit of logic. And function parameter is the fundamental way to control it.so, in theory, __A function parameter is the smallest possible design choice you have to control async vs sync__

There is no way to reduce it further. As you need to encode this somehow, otherwise it will be implicit and very hard to debug.

functions can compose. Function parameters can be composed. Making this a solid design choice.

Zig has somehow achieved this feat of decomposing async/sync to a single parameter. This deserves an ovation Other langs should take note.