Added function for matching hex literals.

src/prelexer.cpp

@@ -107,6 +107,11 @@ namespace Sass {
     char* dimension(char* src) {
       return sequence<number, identifier>(src);
     }
+    char* hex(char* src) {
+      char* p = sequence< exactly<'#'>, one_plus<xdigit> >(src);
+      int len = p - src;
+      return (len != 4 && len != 7) ? 0 : p;
+    }
     // Match CSS uri specifiers.
     extern const char url_call[] = "url(";
     char* uri(char* src) {

src/prelexer.hpp

@@ -228,6 +228,7 @@ namespace Sass {
     char* number(char* src);
     char* percentage(char* src);
     char* dimension(char* src);
+    char* hex(char* src);
     // Match CSS uri specifiers.
     char* uri(char* src);
     // Match CSS function call openers.

src/unit-test-prelexer.cpp

@@ -43,6 +43,10 @@ char pre1[]     = "^='hux'] { ... }";
 char suf1[]     = "$='baz'] { ... }";
 char sub1[]     = "*='bum'] { ... }";
 char ws1[]      = "  /* hello */\t\n//blah\n  /*blah*/ significant";
+char hex1[]     = "#1a2b3c#f1ab";
+char hex2[]     = "#abc-zippo";
+char nonhex1[]  = "#ab blah";
+char nonhex2[]     = "#abc123blah";
 
 extern const char slash_star[] = "/*";
 
@@ -82,6 +86,8 @@ int main() {
   check_twice(suffix_match, suf1, pre1);
   check_twice(substring_match, sub1, suf1);
   check_twice(spaces_and_comments, ws1, num1);
+  check_twice(hex, hex1, nonhex1);
+  check_twice(hex, hex2, nonhex2);
   cout << count_interval<'\n'>(ws1, spaces_and_comments(ws1)) << endl;
   cout << count_interval<'*'>(ws1, spaces_and_comments(ws1)) << endl;
   cout << count_interval<exactly<slash_star> >(ws1, spaces_and_comments(ws1)) << endl;