Simplify OnTerminate.

No, not "awful", AWFUN!

Speaking of AWFUN, here is an alternative implementation of it:

#define AWFUN(t, f) cond_fun<t, f##A, f##W>

template <typename T, auto F, auto G>
std::enable_if_t<std::is_same_v<T, char>, decltype(F)> cond_fun = F;

template <auto F, auto G>
auto cond_fun<wchar_t, F, G> = G;

This implementation uses a variable template instead of a function
template, but I decided against it, as (at least I think) it would
instantiate useless variables that merely point to pre-existing API
functions. Like,

auto cond_fun__wchar_t__blablabla = MessageBoxW;
auto cond_fun__char__blablabla = MessageBoxA;

which is quite useless. Better to just have a constexpr function,
which the compiler may inline, return the real function pointer.

1 files changed, 13 insertions, 0 deletions

diff --git a/c/common.h b/c/common.h
index 0343914..4b42f45 100644
--- a/c/common.h
+++ b/c/common.h
@@ -74,6 +74,19 @@ inline T prefer(const T x)
 	return x;
 }
 
+/* Conditionally select between ANSI and wide string literal. */
+#define AWTEXT(t, s) cond_text<t>(s, L"" s)
+template <typename T> constexpr const T* cond_text(const char*, const wchar_t*);
+template <> constexpr const char* cond_text<char>(const char* sz, const wchar_t*) { return sz; }
+template <> constexpr const wchar_t* cond_text<wchar_t>(const char*, const wchar_t* wsz) { return wsz; }
+
+/* Conditionally select between ANSI and wide Windows API function. */
+#define AWFUN(t, f) cond_fun<t, f##A, f##W>()
+template <typename T, auto F, auto G>
+constexpr std::enable_if_t<std::is_same_v<T, char>, decltype(F)> cond_fun() { return F; }
+template <typename T, auto F, auto G>
+constexpr std::enable_if_t<std::is_same_v<T, wchar_t>, decltype(G)> cond_fun() { return G; }
+
 /* Return integer scaled for current DPI. */
 inline int Dpi(const int i)
 {