2 styles of string literals, using cc-mode

2 styles of string literals, using cc-mode

[yary]

Hi all,

I'm using csharp-mode by Moonfire games ( http://mfgames.com/linux/csharp-mode
), which is derived from cc-mode.

C# has a "feature", two styles of strings. Regular strings are very
much like C strings, starting and ending with double quotes, backslash
escapes allowed inside.

@"Verbatim literal strings look like this"- they have an at-sign just
before the double-quote. Verbatim literal strings can have embedded
newlines, regular strings can't. Backslashes have no special meaning
inside verbatim literals, so:

@"\x00" == "\\x00"
@"foo\" == "foo\\"

I haven't hacked much cc-mode or elisp in general, still it was pretty
simple to get multiline verbatim literals working:

;; Can't escape a newline in a regular string
(c-lang-defconst c-string-escaped-newlines
  csharp nil)

;; Literal strings can be multiline without escaping
(c-lang-defconst c-multiline-string-start-char
  csharp ?@)

I had expected the @ to fontify the same as the " in @" after adding
the following, but these seem to have made no difference:

;; Start of a comment or any string literal- copied from cc-lang,
added @? before \"
(c-lang-defconst c-literal-start-regexp
  csharp (concat (c-lang-const c-comment-start-regexp)
	    "\\|"
	    (if (memq 'gen-string-delim c-emacs-features)
		"@?\"|"
	      "@?\"")))

;; add verbatim string literal to primary regexp
(c-lang-defconst c-primary-expr-regexp
  csharp (concat (c-lang-const c-primary-expr-regexp)
		 "\\|@\""))

... and I have no clue how to tell emacs to change the syntax of \
inside a verbatim literal in csharp mode, so it won't be an escape
anymore. I took a look at cc-engine.el to get a clue as to how it
works, but its elisp is too advanced for me. Any pointers?

Re: 2 styles of string literals, using cc-mode

[jrwats]

On Oct 21, 9:54 am, yary <not....@gmail.com> wrote:
> Hi all,
>
> I'm using csharp-mode by Moonfire games (http://mfgames.com/linux/csharp-mode
> ), which is derived from cc-mode.
>
> C# has a "feature", two styles of strings. Regular strings are very
> much like C strings, starting and ending with double quotes, backslash
> escapes allowed inside.
>
> @"Verbatim literal strings look like this"- they have an at-sign just
> before the double-quote. Verbatim literal strings can have embedded
> newlines, regular strings can't. Backslashes have no special meaning
> inside verbatim literals, so:
>
> @"\x00" == "\\x00"
> @"foo\" == "foo\\"
>
> I haven't hacked much cc-mode or elisp in general, still it was pretty
> simple to get multiline verbatim literals working:
>
> ;; Can't escape a newline in a regular string
> (c-lang-defconst c-string-escaped-newlines
>   csharp nil)
>
> ;; Literal strings can be multiline without escaping
> (c-lang-defconst c-multiline-string-start-char
>   csharp ?@)
>
> I had expected the @ to fontify the same as the " in @" after adding
> the following, but these seem to have made no difference:
>
> ;; Start of a comment or any string literal- copied from cc-lang,
> added @? before \"
> (c-lang-defconst c-literal-start-regexp
>   csharp (concat (c-lang-const c-comment-start-regexp)
>             "\\|"
>             (if (memq 'gen-string-delim c-emacs-features)
>                 "@?\"|"
>               "@?\"")))
>
> ;; add verbatim string literal to primary regexp
> (c-lang-defconst c-primary-expr-regexp
>   csharp (concat (c-lang-const c-primary-expr-regexp)
>                  "\\|@\""))
>
> ... and I have no clue how to tell emacs to change the syntax of \
> inside a verbatim literal in csharp mode, so it won't be an escape
> anymore. I took a look at cc-engine.el to get a clue as to how it
> works, but its elisp is too advanced for me. Any pointers?

ping.  I need this too!  Has anyone figured this out yet?  I suppose I
could start investigating some emacs-lisp source code...