Why not extend do to allow unicode in ID's?

[Bert]

On Sunday, 30 June 2019 at 03:12:55 UTC, sarn wrote:
> D already allows non-latin characters in identifiers, just not 
> arbitrary symbols:
>
> import std.stdio;
>
> void main()
> {
> 	double φ = 1.61803398874989484820;
> 	writeln(φ);
> }

Yeah, I noticed some work but many do not and I'm not even sure 
what does or doesn't ;/