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#include "ObjCWeak.h"
#include <objc/runtime.h>
extern id _Nullable
objc_initWeak(id _Nullable * _Nonnull location, id _Nullable val);
void tryWeakReferencing(id (^makeThing)(void)) {
id thingy;
@autoreleasepool {
thingy = [makeThing() retain];
}
id weakThingy = nil;
objc_initWeak(&weakThingy, thingy);
@autoreleasepool {
fputs("before giving up strong reference:\n", stderr);
id x = objc_loadWeak(&weakThingy);
if (x) {
fputs([[x description] UTF8String], stderr);
fputs("\n", stderr);
} else {
fputs("Gone\n", stderr);
}
}
[thingy release];
thingy = nil;
for (int i = 0; i < 100; i++) {
@autoreleasepool {
id tmp = makeThing();
id weakTmp = nil;
objc_initWeak(&weakTmp, tmp);
objc_loadWeak(&weakTmp);
objc_storeWeak(&weakTmp, nil);
}
}
@autoreleasepool {
fputs("after giving up strong reference:\n", stderr);
id x = objc_loadWeak(&weakThingy);
if (x) {
fputs([[x description] UTF8String], stderr);
fputs("\n", stderr);
} else {
fputs("Gone\n", stderr);
}
}
objc_storeWeak(&weakThingy, nil);
@autoreleasepool {
fputs("after giving up weak reference:\n", stderr);
id x = objc_loadWeak(&weakThingy);
if (x) {
fputs([[x description] UTF8String], stderr);
fputs("\n", stderr);
} else {
fputs("Gone\n", stderr);
}
}
}
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