X-Git-Url: http://git.tdb.fi/?p=libs%2Fcore.git;a=blobdiff_plain;f=source%2Fstrings%2Flexicalcast.cpp;h=2c867b2ce0572b7489a7fb6c9e74013efb6b7804;hp=2fc4be35c182f2d3dde801212580b2329df7a4b1;hb=31cc8f0c6e874e2417e76eda50af34fd17bcd90c;hpb=f24e7b96e76b63c9b9b8a6bce4c7a9db64276ea8

diff --git a/source/strings/lexicalcast.cpp b/source/strings/lexicalcast.cpp
index 2fc4be3..2c867b2 100644
--- a/source/strings/lexicalcast.cpp
+++ b/source/strings/lexicalcast.cpp
@@ -10,12 +10,8 @@ namespace {
 
 using namespace Msp;
 
-template<typename T>
-struct IsSigned
-{ enum { result = !(static_cast<T>(-1)>0) }; };
-
 /* Helper to avoid warnings about an unsigned type never being < 0 */
-template<typename T, bool f = IsSigned<T>::result>
+template<typename T, bool f = is_signed<T>::value>
 struct IsNegative
 { static bool eval(T v) { return v<0; } };
 
@@ -23,9 +19,17 @@ template<typename T>
 struct IsNegative<T, false>
 { static bool eval(T) { return false; } };
 
+template<typename T, bool f = is_signed<T>::value>
+struct Negate
+{ static T eval(T v) { return -v; } };
+
+template<typename T>
+struct Negate<T, false>
+{ static T eval(T v) { return (~v)+1; } };
+
 /* Helper to avoid errors about ambiguous function calls since there are no
 overloads of abs for unsigned types */
-template<typename T, bool f = IsSigned<T>::result>
+template<typename T, bool f = is_signed<T>::value>
 struct Absolute
 { static T eval(T v) { return v<0 ? -v : v; } };
 
@@ -119,7 +123,7 @@ T str_to_int(const string &s, const Fmt &f)
 	bool neg = false;
 	if(*i=='-')
 	{
-		if(!IsSigned<T>::result)
+		if(is_unsigned<T>::value)
 			throw lexical_error(format("conversion of '%s' to unsigned integer", s));
 		neg = true;
 		++i;
@@ -174,7 +178,7 @@ T str_to_int(const string &s, const Fmt &f)
 	}
 
 	if(neg)
-		result = -result;
+		result = Negate<T>::eval(result);
 
 	return result;
 }