Run on the main thread. If we're already there, run synchronously.

gistfile1.txt

@implementation NSOperationQueue (BHSAdditions)

+ (void)bhs_runOnMainQueue:(void (^)(void))block {
    NSParameterAssert(block);
    if ([NSThread isMainThread]) {
        block();
    } else {
        [[self mainQueue] addOperationWithBlock:block];
    }
}

@end