swifty_errors.m

#import <Foundation/Foundation.h>

#define Attempt(...) ({ \
    NSError *__err; \
    typeof([__VA_ARGS__ error:NULL]) __result = [__VA_ARGS__ error:&__err]; \
    if(!__result) \
        @throw __err; \
    __result; \
})

int main(int argc, char *argv[]) {
    @autoreleasepool {
        @try {
            NSString *str = Attempt(NSString stringWithContentsOfFile:@"foo" encoding:NSUTF8StringEncoding);
        } @catch(NSError *err) {
            NSLog(@"%@", err);
        }
    }
}