Added (conditional) SFINAE support.

Better streamable detection for toString using SFINAE (falls back to non-SFINAE version without)

include/internal/catch_compiler_capabilities.h

@@ -0,0 +1,74 @@
+/*
+ *  Created by Phil on 15/04/2013.
+ *  Copyright 2013 Two Blue Cubes Ltd. All rights reserved.
+ *
+ *  Distributed under the Boost Software License, Version 1.0. (See accompanying
+ *  file LICENSE_1_0.txt or copy at http://www.boost.org/LICENSE_1_0.txt)
+ */
+#ifndef TWOBLUECUBES_CATCH_COMPILER_CAPABILITIES_HPP_INCLUDED
+#define TWOBLUECUBES_CATCH_COMPILER_CAPABILITIES_HPP_INCLUDED
+
+// Much of the following code is based on Boost (1.53)
+
+////////////////////////////////////////////////////////////////////////////////
+// Borland
+#ifdef __BORLANDC__
+
+#if (__BORLANDC__ > 0x582 )
+#define CATCH_SFINAE
+#endif
+
+#endif // __BORLANDC__
+
+////////////////////////////////////////////////////////////////////////////////
+// EDG
+#ifdef __EDG_VERSION__
+
+#if (__EDG_VERSION__ > 238 )
+#define CATCH_SFINAE
+#endif
+
+#endif // __EDG_VERSION__
+
+////////////////////////////////////////////////////////////////////////////////
+// Digital Mars
+#ifdef __DMC__
+
+#if (__DMC__ > 0x840 )
+#define CATCH_SFINAE
+#endif
+
+#endif // __DMC__
+
+////////////////////////////////////////////////////////////////////////////////
+// GCC
+#ifdef __GNUC__
+
+#if __GNUC__ < 3
+
+#if (__GNUC_MINOR__ >= 96 )
+#define CATCH_SFINAE
+#endif
+
+#elif __GNUC__ >= 3
+
+#define CATCH_SFINAE
+
+#endif // __GNUC__ < 3
+
+
+#endif // __GNUC__
+
+////////////////////////////////////////////////////////////////////////////////
+// Visual C++
+#ifdef _MSC_VER
+
+#if (_MSC_VER >= 1310 ) // (VC++ 7.0+)
+#define CATCH_SFINAE
+#endif
+
+#endif // _MSC_VER
+
+
+#endif // TWOBLUECUBES_CATCH_COMPILER_CAPABILITIES_HPP_INCLUDED
+