Is Swift optional chaining always done with the if let construction, or is it just done using a question mark with an optional?
问题 As per Apple docs, optional chaining is the following: You specify optional chaining by placing a question mark (?) after the optional value on which you wish to call a property, method or subscript if the optional is non-nil. ... optional chaining fails gracefully when the optional is nil ... My interpretation of this is that a construction as the following is optional chaining: someMasterObject.possiblyNilHandler?.handleTheSituation() ...and that the above line would call the