Printing of "\n" in error messages is broken
The code excerpts in error messages from GHC 7.8.3 are misformatted when the original code contains the string "\n" - the \n escape is simply lost. Example with GHCi:
Prelude> 1+"\n" <interactive>:2:2: No instance for (Num [Char]) arising from a use of `+' In the expression: 1 + "" In an equation for `it': it = 1 + ""
The printing of the string "\n " is also strangely formatted, although technically equivalent:
Prelude> 1+"\n " <interactive>:3:2: No instance for (Num [Char]) arising from a use of `+' In the expression: 1 + "\n\ \ " In an equation for `it': it = 1 + "\n\ \ "