Upper-cased raw strings not supported

[FichteFoll]

var = R"I'm a raw string"

E:\Temp>mypy upper_case_raw.py
upper_case_raw.py:1: error: Unterminated string literal

I believe this will be solved by the updated parser (#1353) but couldn't verify since I was unable to install the typed-ast pypi module on my Windows machine (no binary wheels and couldn't compile).

[gvanrossum]

Yeah, the new parser fixes this.

[ddfisher]

(And FYI we're working on making typed-ast work on Windows soon.)

[gvanrossum]

I'm going to close this as a won't fix because the new parser will solve this and we're not going to put any work in the old parser/lexer.