>> I have prepared a draft SRFI for raw string literals. The draft is
>> here: https://github.com/lloda/guile-raw-strings/blob/master/srfi.md,
>> but I describe the general ideal below.

You may or may not want to add it to our unofficial pre-SRFI collection
for early review:

https://github.com/pre-srfi

#r syntax has prior applications in Scheme and Common Lisp:

https://registry.scheme.org/#hash-syntax

http://clhs.lisp.se/Body/02_dh.htm

Lisp has an unusually sparse lexical syntax, so expect pushback against
any suggestions for new syntax. But the SRFI process will host any
reasonably presented proposal.

> I suggest taking a look at the extended string literals of SRFI-109
> (https://srfi.schemers.org/srfi-109/srfi-109.html).
> They are implemented in Kawa.
>
> SRFI-109 literals reduce the issue with nested escapes.
> One reason is you can use the delimters '{' and ']' in
> the string without quoting as long as they're nested properly.

+1