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Added private GSFastEnumeration header. This defines two macros that allow fast enumeration to be used inside GNUstep. Use, for example:

Browse source 
NSArray *a=  [NSArray arrayWithObjects: @"a", @"b", @"c", nil];
FOR_IN(NSString*, o, a)
	NSLog(@"%@", o);
END_FOR_IN(a)

This is equivalent to:

for (NSString *o in a)
{
	NSLog(@"%@", o);
}

On clang, it will be expanded to exactly that.  With GCC, it will be expanded to something equivalent to the code that Clang (or Apple GCC) would expand this to.

This is a private GNUstep header and is not intended for general use.  Outside of GNUstep, please use fast enumeration directly.



git-svn-id: svn+ssh://svn.gna.org/svn/gnustep/libs/base/trunk@29170 72102866-910b-0410-8b05-ffd578937521
This commit is contained in:
David Chisnall 2009-12-27 14:34:10 +00:00
parent 2c401de4f4
commit ea5f15deb0
2 changed files with 41 additions and 0 deletions
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37
Source/GSFastEnumeration.h Normal file
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#ifdef __clang__
#define FOR_IN(type, var, collection) \
for (type var in collection)
#define END_FOR_IN(collection) }
#else
#define FOR_IN(type, var, c) \
do\
{\
type var;\
volatile NSFastEnumerationState gs_##c##_enumState = { 0 };\
id gs_##c##_items[16];\
unsigned long gs_##c##_limit = \
[c countByEnumeratingWithState: &gs_##c##_enumState \
objects: gs_##c##_items \
count: 16];\
if (gs_##c##_limit)\
{\
unsigned long gs_startMutations = *gs_##c##_enumState.mutationsPtr;\
do {\
unsigned long gs_##c##counter = 0;\
do {\
if (gs_startMutations != *gs_##c##_enumState.mutationsPtr)\
{\
objc_enumerationMutation(c);\
}\
var = gs_##c##_enumState.itemsPtr[gs_##c##counter++];\
#define END_FOR_IN(c) \
} while (gs_##c##counter < gs_##c##_limit);\
} while (gs_##c##_limit = [c countByEnumeratingWithState: &gs_##c##_enumState\
objects: gs_##c##_items\
count: 16]);\
}\
} while(0);
#endif