I think there is a possible design for them that is not too bad, but it would need named parameters. I think the time o encountered that idea was part of a longer post about solving a different problem in Rust.
But i doubt it would be an urgent thing to change.
Tldr: add named arguments (optional). You can call with anon names, in which case it is positional as it is today. If you use named arguments to call, you have to use them in the order they have been declared, just like with positional, but you _can_ omit some. These get the default value.
There are ofc combinations that could be allowed, like anon until the first optional one, whatever.
But i doubt it would be an urgent thing to change.
Tldr: add named arguments (optional). You can call with anon names, in which case it is positional as it is today. If you use named arguments to call, you have to use them in the order they have been declared, just like with positional, but you _can_ omit some. These get the default value.
There are ofc combinations that could be allowed, like anon until the first optional one, whatever.
It was part of this post, but don't it was a solution to a different problem kinda (and kinda not technically) https://faultlore.com/blah/defaults-affect-inference/