diff --git a/include/chaiscript/chaiscript_defines.hpp b/include/chaiscript/chaiscript_defines.hpp
index 0a76a82..97f969f 100644
--- a/include/chaiscript/chaiscript_defines.hpp
+++ b/include/chaiscript/chaiscript_defines.hpp
@@ -144,21 +144,6 @@ namespace chaiscript {
   };
 
 
-  template<typename T>
-    auto parse_num(const char *t_str) -> typename std::enable_if<std::is_integral<T>::value, T>::type
-    {
-      T t = 0;
-      for (char c = *t_str; (c = *t_str) != 0; ++t_str) {
-        if (c < '0' || c > '9') {
-          return t;
-        }
-        t *= 10;
-        t += c - '0';
-      }
-      return t;
-    }
-
-
   template<typename T>
     auto parse_num(const char *t_str) -> typename std::enable_if<!std::is_integral<T>::value, T>::type
     {
@@ -176,6 +161,16 @@ namespace chaiscript {
         }
       };
 
+      const bool neg = [&](){
+        if (t_str[0] == '-') {
+          ++t_str;
+          return true;
+        } else {
+          return false;
+        }
+      }();
+
+
       for(; *t_str != '\0'; ++t_str) {
         char c = *t_str;
         if (c == '.') {
@@ -200,7 +195,7 @@ namespace chaiscript {
         }
       }
 
-      return final_value(t, base, exponent, neg_exponent);
+      return final_value(t, base, exponent, neg_exponent) * (neg?-1:1);
     }
 
   template<typename T>
diff --git a/include/chaiscript/language/chaiscript_parser.hpp b/include/chaiscript/language/chaiscript_parser.hpp
index 3e7315b..fe275ec 100644
--- a/include/chaiscript/language/chaiscript_parser.hpp
+++ b/include/chaiscript/language/chaiscript_parser.hpp
@@ -722,7 +722,10 @@ namespace chaiscript
           }
         }
 
-        const auto val = prefixed?std::string(t_val.begin()+2,t_val.end()):t_val;
+
+        const bool neg = t_val[0] == '-';
+        const auto pref = neg?std::string(t_val.begin()+1,t_val.end()):t_val;
+        const auto val = prefixed?std::string(pref.begin() + 2, pref.end()):pref;
 
 #ifdef __GNUC__
 #pragma GCC diagnostic push
@@ -739,17 +742,17 @@ namespace chaiscript
 
 
           if (!unsigned_ && !long_ && u >= std::numeric_limits<int>::min() && u <= std::numeric_limits<int>::max()) {
-            return const_var(static_cast<int>(u));
+            return const_var(static_cast<int>(u) * (neg?-1:1));
           } else if ((unsigned_ || base != 10) && !long_ && u >= std::numeric_limits<unsigned int>::min() && u <= std::numeric_limits<unsigned int>::max()) {
-            return const_var(static_cast<unsigned int>(u));
+            return const_var(static_cast<unsigned int>(u) * (neg?-1:1));
           } else if (!unsigned_ && !longlong_ && u >= std::numeric_limits<long>::min() && u <= std::numeric_limits<long>::max()) {
-            return const_var(static_cast<long>(u));
+            return const_var(static_cast<long>(u) * (neg?-1:1));
           } else if ((unsigned_ || base != 10) && !longlong_ && u >= std::numeric_limits<unsigned long>::min() && u <= std::numeric_limits<unsigned long>::max()) {
-            return const_var(static_cast<unsigned long>(u));
+            return const_var(static_cast<unsigned long>(u) * (neg?-1:1));
           } else if (!unsigned_ && u >= std::numeric_limits<long long>::min() && u <= std::numeric_limits<long long>::max()) {
-            return const_var(static_cast<long long>(u));
+            return const_var(static_cast<long long>(u) * (neg?-1:1));
           } else {
-            return const_var(static_cast<unsigned long long>(u));
+            return const_var(static_cast<unsigned long long>(u) * (neg?-1:1));
           }
 
         } catch (const std::out_of_range &) {
@@ -758,13 +761,13 @@ namespace chaiscript
             auto u = std::stoull(val,nullptr,base);
 
             if (u >= std::numeric_limits<unsigned long>::min() && u <= std::numeric_limits<unsigned long>::max()) {
-              return const_var(static_cast<unsigned long>(u));
+              return const_var(static_cast<unsigned long>(u) * (neg?-1:1));
             } else {
-              return const_var(static_cast<unsigned long long>(u));
+              return const_var(static_cast<unsigned long long>(u) * (neg?-1:1));
             }
           } catch (const std::out_of_range &) {
             // it's just simply too big
-            return const_var(std::numeric_limits<long long>::max());
+            return const_var(neg?std::numeric_limits<long long>::min():std::numeric_limits<long long>::max());
           }
         }
 
@@ -785,6 +788,7 @@ namespace chaiscript
         SkipWS();
 
         const auto start = m_position;
+        const bool neg = Char_('-');
         if (m_position.has_more() && char_in_alphabet(*m_position, detail::float_alphabet) ) {
           try {
             if (Hex_()) {
@@ -809,7 +813,7 @@ namespace chaiscript
             else {
               IntSuffix_();
               auto match = Position::str(start, m_position);
-              if (!match.empty() && (match[0] == '0')) {
+              if (!match.empty() && (match[neg?1:0] == '0')) {
                 auto bv = buildInt(8, match, false);
                 m_match_stack.push_back(make_node<eval::Constant_AST_Node<Tracer>>(std::move(match), start.line, start.col, std::move(bv)));
               }
@@ -827,6 +831,7 @@ namespace chaiscript
           }
         }
         else {
+          if (neg) { --m_position; }
           return false;
         }
       }
diff --git a/include/chaiscript/utility/json.hpp b/include/chaiscript/utility/json.hpp
index 96decc0..73a0c98 100644
--- a/include/chaiscript/utility/json.hpp
+++ b/include/chaiscript/utility/json.hpp
@@ -600,7 +600,7 @@ struct JSONParser {
           break;
 }
       }
-      exp = chaiscript::parse_num<long>( exp_str );
+      exp = std::stol( exp_str );
     }
     else if( offset < str.size() && (!isspace( c ) && c != ',' && c != ']' && c != '}' )) {
       throw std::runtime_error(std::string("JSON ERROR: Number: unexpected character '") + c + "'");
@@ -611,9 +611,9 @@ struct JSONParser {
       return JSON(chaiscript::parse_num<double>( val ) * std::pow( 10, exp ));
     } else {
       if( !exp_str.empty() ) {
-        return JSON(static_cast<double>(chaiscript::parse_num<long>( val )) * std::pow( 10, exp ));
+        return JSON(static_cast<double>(std::stol( val )) * std::pow( 10, exp ));
       } else {
-        return JSON(chaiscript::parse_num<long>( val ));
+        return JSON(std::stol( val ));
       }
     }
   }