Proposal: remove string gaps

String gaps are barely necessary, being only a small syntactic convenience. e.g.

f = "abc\
    \def"

can be written

f = "abc" ++
    "def"

GHC compiles the same code in both cases.

Pros

simplifies the lexical syntax (good for automatic syntax colouring tools, which often get string gaps wrong).
a better alternative is HereDocuments?
string gaps cause problems with CPP, which doesn't like the backslash at the end of the line. (a minor consideration, since CPP is not part of the language, and in any case there is cpphs).

string gaps are sometimes really helpful for formatting/pretty printing code neatly; the ++ alternative often necessecitates additional bracketing
breaks some code
the simplification of the lexical syntax is very minor
arguably, the syntax highlighting ought to be fixed as that's what at fault, not the language as such
naive compilers won't implement the optimisation, and hence will perform an unnecessary append.