}
+namespace {
+
+inline
+bool isHexChar(char_type c)
+{
+ return c == '0' ||
+ c == '1' ||
+ c == '2' ||
+ c == '3' ||
+ c == '4' ||
+ c == '5' ||
+ c == '6' ||
+ c == '7' ||
+ c == '8' ||
+ c == '9' ||
+ c == 'a' || c == 'A' ||
+ c == 'b' || c == 'B' ||
+ c == 'c' || c == 'C' ||
+ c == 'd' || c == 'D' ||
+ c == 'e' || c == 'E' ||
+ c == 'f' || c == 'F';
+}
+
+} // anon namespace
+
+
+bool isHex(docstring const & str)
+{
+ int index = 0;
+
+ if (str.length() > 2 && str[0] == '0' &&
+ (str[1] == 'x' || str[1] == 'X'))
+ index = 2;
+
+ int const len = str.length();
+
+ for (; index < len; ++index) {
+ if (!isHexChar(str[index]))
+ return false;
+ }
+ return true;
+}
+
+
+int hexToInt(docstring const & str)
+{
+ string s = to_ascii(str);
+ int h;
+ sscanf(s.c_str(), "%x", &h);
+ return h;
+}
+
+
+bool isAscii(docstring const & str)
+{
+ int const len = str.length();
+ for (int i = 0; i < len; ++i)
+ if (str[i] >= 0x80)
+ return false;
+ return true;
+}
+
+
char lowercase(char c)
{
return char(tolower(c));