diff --git a/src/Lexer.cpp b/src/Lexer.cpp
index 9b399fec7..df8af936d 100644
--- a/src/Lexer.cpp
+++ b/src/Lexer.cpp
@@ -159,15 +159,6 @@ bool Lexer::isDigit (int c)
   return c >= 0x30 && c <= 0x39;
 }
 
-////////////////////////////////////////////////////////////////////////////////
-// Digits 0-9 a-f A-F.
-bool Lexer::isHexDigit (int c)
-{
-  return (c >= '0' && c <= '9') ||
-         (c >= 'a' && c <= 'f') ||
-         (c >= 'A' && c <= 'F');
-}
-
 ////////////////////////////////////////////////////////////////////////////////
 bool Lexer::isIdentifierStart (int c)
 {
@@ -581,7 +572,7 @@ bool Lexer::isUUID (std::string& token, Lexer::Type& type, bool endBoundary)
   {
     if (uuid_pattern[i] == 'x')
     {
-      if (! isHexDigit (_text[marker + i]))
+      if (! unicodeHexDigit (_text[marker + i]))
         break;
     }
     else if (uuid_pattern[i] != _text[marker + i])
@@ -616,7 +607,7 @@ bool Lexer::isHexNumber (std::string& token, Lexer::Type& type)
   {
     marker += 2;
 
-    while (isHexDigit (_text[marker]))
+    while (unicodeHexDigit (_text[marker]))
       ++marker;
 
     if (marker - _cursor > 2)
@@ -1469,10 +1460,10 @@ bool Lexer::readWord (
     else if (eos - cursor >= 6 &&
              ((text[cursor + 0] == 'U'  && text[cursor + 1] == '+') ||
               (text[cursor + 0] == '\\' && text[cursor + 1] == 'u')) &&
-             isHexDigit (text[cursor + 2]) &&
-             isHexDigit (text[cursor + 3]) &&
-             isHexDigit (text[cursor + 4]) &&
-             isHexDigit (text[cursor + 5]))
+             unicodeHexDigit (text[cursor + 2]) &&
+             unicodeHexDigit (text[cursor + 3]) &&
+             unicodeHexDigit (text[cursor + 4]) &&
+             unicodeHexDigit (text[cursor + 5]))
     {
       word += utf8_character (
                 hexToInt (
@@ -1553,10 +1544,10 @@ bool Lexer::readWord (
     else if (eos - cursor >= 6 &&
              ((text[cursor + 0] == 'U'  && text[cursor + 1] == '+') ||
               (text[cursor + 0] == '\\' && text[cursor + 1] == 'u')) &&
-             isHexDigit (text[cursor + 2]) &&
-             isHexDigit (text[cursor + 3]) &&
-             isHexDigit (text[cursor + 4]) &&
-             isHexDigit (text[cursor + 5]))
+             unicodeHexDigit (text[cursor + 2]) &&
+             unicodeHexDigit (text[cursor + 3]) &&
+             unicodeHexDigit (text[cursor + 4]) &&
+             unicodeHexDigit (text[cursor + 5]))
     {
       word += utf8_character (
                 hexToInt (
diff --git a/src/Lexer.h b/src/Lexer.h
index fe8b80e59..f5438bf31 100644
--- a/src/Lexer.h
+++ b/src/Lexer.h
@@ -63,7 +63,6 @@ public:
   static const std::string typeName          (const Lexer::Type&);
   static bool isAlpha                        (int);
   static bool isDigit                        (int);
-  static bool isHexDigit                     (int);
   static bool isIdentifierStart              (int);
   static bool isIdentifierNext               (int);
   static bool isSingleCharOperator           (int);