I want to execute two functions - lets say functionA and functionB.I need functionA to finish executing before funcB executes because functionB uses data from functionA. I thought I would use DispatchQueue.main.async to accomplish this... DispatchQueue.main.async(execute: { self.functionA() self.functionB() }) When I use it, functionA gets executed, but functionB does not get executed. I'd appreciate any help.Thanks