No escape chars in character classes

src/re.cpp

@@ -233,14 +233,6 @@ namespace lxs {
                         last_char = -1;
                     }
                 }
-                else if (input[idx] == '\\')
-                {
-                    idx++;
-                    if (idx >= input.size())
-                        throw SyntaxError("Unclosed character classe");
-                    last_char = parseEscapeChar(input[idx]);
-                    used_chars.insert(last_char);
-                }
                 else
                 {
                     used_chars.insert(input[idx]);