Pure/Constant Interpolated Strings

[TonyValenti]

It would be great if I could do this:

const string V1 = "test";
const double V2 = 123.45678;
const string V3 = #"I am {V1}ing this out {V2:0.00} times.";

My understanding is that currently $"" does some culture-specific stuff. It would be great if # could be used to generate const-ish strings devoid of any culture applications (invariant culture?)

[HaloFour]

#2951

[canton7]

Also #384/#2077 and #177/#3044