mirror of
https://github.com/scratchfoundation/bgfx.git
synced 2024-11-25 09:08:22 -05:00
68 lines
2.1 KiB
C++
68 lines
2.1 KiB
C++
// This code is in the public domain -- Ignacio Castaño <castano@gmail.com>
|
|
|
|
#pragma once
|
|
#ifndef NV_CORE_FOREACH_H
|
|
#define NV_CORE_FOREACH_H
|
|
|
|
/*
|
|
These foreach macros are very non-standard and somewhat confusing, but I like them.
|
|
*/
|
|
|
|
#include "nvcore.h"
|
|
|
|
#if NV_CC_GNUC // If typeof or decltype is available:
|
|
#if !NV_CC_CPP11
|
|
# define NV_DECLTYPE typeof // Using a non-standard extension over typeof that behaves as C++11 decltype
|
|
#else
|
|
# define NV_DECLTYPE decltype
|
|
#endif
|
|
|
|
/*
|
|
Ideally we would like to write this:
|
|
|
|
#define NV_FOREACH(i, container) \
|
|
for(NV_DECLTYPE(container)::PseudoIndex i((container).start()); !(container).isDone(i); (container).advance(i))
|
|
|
|
But gcc versions prior to 4.7 required an intermediate type. See:
|
|
https://gcc.gnu.org/bugzilla/show_bug.cgi?id=6709
|
|
*/
|
|
|
|
#define NV_FOREACH(i, container) \
|
|
typedef NV_DECLTYPE(container) NV_STRING_JOIN2(cont,__LINE__); \
|
|
for(NV_STRING_JOIN2(cont,__LINE__)::PseudoIndex i((container).start()); !(container).isDone(i); (container).advance(i))
|
|
|
|
#else // If typeof not available:
|
|
|
|
#include <new> // placement new
|
|
|
|
struct PseudoIndexWrapper {
|
|
template <typename T>
|
|
PseudoIndexWrapper(const T & container) {
|
|
nvStaticCheck(sizeof(typename T::PseudoIndex) <= sizeof(memory));
|
|
new (memory) typename T::PseudoIndex(container.start());
|
|
}
|
|
// PseudoIndex cannot have a dtor!
|
|
|
|
template <typename T> typename T::PseudoIndex & operator()(const T * /*container*/) {
|
|
return *reinterpret_cast<typename T::PseudoIndex *>(memory);
|
|
}
|
|
template <typename T> const typename T::PseudoIndex & operator()(const T * /*container*/) const {
|
|
return *reinterpret_cast<const typename T::PseudoIndex *>(memory);
|
|
}
|
|
|
|
uint8 memory[4]; // Increase the size if we have bigger enumerators.
|
|
};
|
|
|
|
#define NV_FOREACH(i, container) \
|
|
for(PseudoIndexWrapper i(container); !(container).isDone(i(&(container))); (container).advance(i(&(container))))
|
|
|
|
#endif
|
|
|
|
// Declare foreach keyword.
|
|
#if !defined NV_NO_USE_KEYWORDS
|
|
# define foreach NV_FOREACH
|
|
# define foreach_index NV_FOREACH
|
|
#endif
|
|
|
|
|
|
#endif // NV_CORE_FOREACH_H
|