From: Mikko Rasa <tdb@tdb.fi>
Date: Wed, 1 Aug 2012 15:01:10 +0000 (+0300)
Subject: Provide a way to get an integer type matching the size of another type
X-Git-Url: http://git.tdb.fi/?p=libs%2Fcore.git;a=commitdiff_plain;h=c29459b08eca95418fbdee714a1c59f3becdb2ce

Provide a way to get an integer type matching the size of another type
---

diff --git a/source/core/inttypes.h b/source/core/inttypes.h
index 3bdac35..58debd0 100644
--- a/source/core/inttypes.h
+++ b/source/core/inttypes.h
@@ -46,6 +46,11 @@ struct Int
 	typedef typename TypeChooser<PlatformUnsignedTypes, Predicate>::Type UnsignedType;
 };
 
+/** A helper for choosing an integer that's the same size as another type. */
+template<typename T>
+struct MatchingInt: Int<sizeof(T)*CHAR_BIT>
+{ };
+
 // Finally define convenient shorthands for the actual integer types
 typedef Int<8>::SignedType Int8;
 typedef Int<8>::UnsignedType UInt8;
@@ -55,6 +60,7 @@ typedef Int<32>::SignedType Int32;
 typedef Int<32>::UnsignedType UInt32;
 typedef Int<64>::SignedType Int64;
 typedef Int<64>::UnsignedType UInt64;
+typedef MatchingInt<void *>::UnsignedType IntPtr;
 
 } // namespace Msp
 
diff --git a/source/strings/lexicalcast.cpp b/source/strings/lexicalcast.cpp
index 71e346b..6a226e1 100644
--- a/source/strings/lexicalcast.cpp
+++ b/source/strings/lexicalcast.cpp
@@ -14,16 +14,6 @@ template<typename T>
 struct IsSigned
 { enum { result = !(static_cast<T>(-1)>0) }; };
 
-template<typename T, bool f = (sizeof(T)>sizeof(unsigned long))>
-struct Temporary
-{ typedef unsigned long Type; };
-
-template<typename T>
-struct Temporary<T, true>
-{
-	typedef UInt64 Type;
-};
-
 /* Helper to avoid warnings about an unsigned type never being < 0 */
 template<typename T, bool f = IsSigned<T>::result>
 struct IsNegative
@@ -69,7 +59,7 @@ char *int_to_str(T v, const Fmt &f, char *end)
 	const char *digits = (f.get_uppercase() ? udigits : ldigits);
 	if(v)
 	{
-		typename Temporary<T>::Type w = Absolute<T>::eval(v);
+		typename MatchingInt<T>::UnsignedType w = Absolute<T>::eval(v);
 		while(w)
 		{
 			*--ptr = digits[w%base];
@@ -544,7 +534,7 @@ void operator<<(LexicalConverter &c, const char *s)
 { c.result(str_to_str(s, c.get_fmt())); }
 
 void operator<<(LexicalConverter &c, const void *p)
-{ c.result(int_to_str(reinterpret_cast<unsigned long>(p), c.get_fmt())); }
+{ c.result(int_to_str(reinterpret_cast<IntPtr>(p), c.get_fmt())); }
 
 
 /*** operator>> ***/