Swift Function

    func functionVoid() {

    }

    func declareFunction() {

        functionVoid()

        let functionVoidWithParameter: () = functionVoid()
        // CORRECT EXECTION
        functionVoidWithParameter

        let functionVoidWithoutParameter: () -> () = functionVoid
        // CORRECT EXECTION
        functionVoidWithoutParameter()

    }

    func functionString(string: String) {
        print(string)
    }

    func getStringFunctionInsideParameters() {
        let string: String = "Teste"
        let function: () = functionString(string: string)
        return function
    }

    func getStringFunctionOutsideParameters() -> (String) -> () {
        let function = functionString
        return function
    }

    func someFunction() {

        let internalInjectionFunction: () = getStringFunctionInsideParameters()
        internalInjectionFunction

        let externalInjectionFunction = getStringFunctionOutsideParameters()
        externalInjectionFunction("Teste")

    }