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@cdzombak
Last active January 7, 2016 16:05
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if-let in ObjC
#import <Foundation/Foundation.h>
#define iflet(LHS, RHS) \
for (id obj_ = (RHS); obj_ != nil;) \
for (LHS = (obj_ ?: (RHS)); obj_ != nil; obj_ = nil)
int main(int argc, char *argv[]) {
@autoreleasepool {
NSString *x = nil;
NSString *y = @"y";
iflet(NSString *z, x) {
NSLog(@"x is non-nil: %@", z);
}
iflet(NSString *z, y) {
NSLog(@"y is non-nil: %@", z);
}
}
}
/* outputs:
Untitled[44105:2794964] y is non-nil: y
*/
@cdzombak
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@CraigSiemens
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Do you have a way to add an else case? This is what I came up with and it seems to work but I'm not sure if I overlooked anything.

#define iflet(LHS, RHS) \
    for (BOOL b_ = YES; b_ != NO;) \
        for (id obj_ = (RHS); b_ != NO;) \
            for (LHS = (obj_ ?: (RHS)); b_ != NO; b_ = NO) \
                if (obj_ != nil)

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