golang_interface_totality.go

// Creating a Simple Interface "Employee"
type Employee interface {
  GetDetails() string
  GetEmployeeSalary() int
}

// Creating a new type "Manager" containing all functions required by "Employee" Interface
type Manager struct {
  Name string
  Age int
  Designation string 
  Salary int
}

func (mgr Manager) GetDetails() string {
  return mgr.Name + " " + mgr.Age;
}

func (mgr Manager) GetEmployeeSalary int {
  return mgr.Salary
}

// Creating new Object of Type Manager
newManager := Manager{Name: "Mayank", Age: 30, Designation: "Developer" Salary: 10}

// New variable of type "Employee" created
var employeeInterface Employee

//Manager Object assigned to Interface type since Interface Contract is satisfied
employeeInterface = newManager

// Invoke Functions that belong to Interface "Employee"
employeeInterface.GetDetails()

L20 misses parentheses for function

L25 misses ,
nevertheless, a great example!