String interpolation

[Champii]

`${foo}, ${bar}`.print!

This could desugar to:

"${0}, ${1}".format foo, bar .print!

I think it is important to introduce a new syntactic construct here with the back-quote '`', to also allow users to construct raw strings that would not be interpolated.

"${foo}, ${bar}".print!

This would just print the string as is, without interpolation.

Originally posted by @Champii in #122 (comment)