What is your evaluation of the proposal?
I am +1 for the principle. I am not sure if raw of the best name. I am used to calling these verbatim strings from c# https://docs.microsoft.com/en-us/dotnet/csharp/language-reference/tokens/verbatim.
I think r"" is unfortunate because we do not yet have regex literals. I do not think that r is the best letter for this because of regex. I would rather have something more verbose like #verbatimString("") then once we decide how regex will be spelled then we can have shortcuts like @"" or #"" etc
Is the problem being addressed significant enough to warrant a change to Swift?
Yes. I love verbatim string in c# and I think I would use them a lot in swift if available.
Does this proposal fit well with the feel and direction of Swift?
yes. This name should be long to start with then we can shorten it once the regex syntax gets cooked.
If you have used other languages or libraries with a similar feature, how do you feel that this proposal compares to those?
How much effort did you put into your review? A glance, a quick reading, or an in-depth study?
read proposal and implementation.