Open Radar

 
Summary:
Other programming languages provide a "raw" string literal that can be used to define a string containing "special characters" without the need to escape each one.  This is useful when using regular expressions or other inline code that contains backslashes or double-quote characters.

Other programming languages also allow string literals to span multiple lines. Again, this is helpful when using regular expressions, template substitution, and other programming techniques that require long strings with embedded newlines.

Currently in Swift, one must escape all special characters, and defining a multi-line string requires quoting each line and using + to concatenate them. Swift should provide raw string literals and multiline string literals.

Steps to Reproduce:
Try to define a regular expression in Swift using code like this copied from source in another programming language:

let myRegexPattern = @"
^[ ]{{0,{0}}}\[([^\[\]]+)\]:  # id = $1
  [ ]*
  \n?                   # maybe *one* newline
  [ ]*
<?(\S+?)>?              # url = $2
  [ ]*
  \n?                   # maybe one newline
  [ ]*
(?:
    (?<=\s)             # lookbehind for whitespace
    [""(]
    (.+?)               # title = $3
    ["")]
    [ ]*
)?                      # title is optional
(?:\n+|\Z)
"


Expected Results:
Should be easy

Actual Results:
Compiler errors. One has to rewrite it like this (and I'm not sure I escaped everything properly):

let myRegexPattern = "
"^[ ]{{0,{0}}}\[([^\\[\\]]+)\\]:  # id = $1 \n" +
"  [ ]* \n" +
"  \\n?                   # maybe *one* newline \n" +
"  [ ]* \n" +
"<?(\S+?)>?              # url = $2 \n" +
"  [ ]* \n" +
"  \\n?                   # maybe one newline \n" +
"  [ ]* \\n" +
"(?: \n" +
"    (?<=\\s)             # lookbehind for whitespace \n" +
"    [\"(] \n" +
"    (.+?)               # title = $3 \n" +
"    [\")] \n" +
"    [ ]* \n" +
")?                      # title is optional \n" +
"(?:\\n+|\\Z) \n"

Version:
Xcode 6.0 (6A279r)

Notes:


Configuration:
OS X 10.9

Attachments: