On an authentication view, there are some inputs, like password, email, etc and a sign up button which is enabled only if theses inputs are not empty.So what I have is this function: func canSignUpButtonBeEnabled() -> Bool {    let password = self.passwordTextField.text.stringByReplacingOccurrencesOfString( , withString: )    return (!self.emailTextField.text.isEmpty && !self.passwordTextField.text.isEmpty            && !self.firstNameTextField.text.isEmpty  && !self.lastNameTextField.text.isEmpty            && countElements(password) >= 4)}And after each character entered by the user, I set on the enable property of my button the result of this function.So I was wondering if there is a cleaner solution to do it?
Validating conditions for enabling sign-up button
form;swift