Showcase: begin_fix

The trick behind this uses template and C++ overloads. So that every encoding works.

	namespace detail
	{
		template <typename char_type= char>
		const char_type* begin_fix();

		template <>
		inline const char* begin_fix<char>()
		{
			return "FIX.4.2";
		}

		template <>
		inline const char16_t* begin_fix<char16_t>()
		{
			return u"FIX.4.2";
		}

		template <>
		inline const char8_t* begin_fix<char8_t>()
		{
			return u8"FIX.4.2";
		}
	} // namespace detail

Amlal.