Learning Functional Programming in Go

Testing iterators for element equality

First, let's create the testIterEq function to test whether two collections are equivalent:

func testIterEq(t *testing.T, it1, it2 Iter) {     t.Log("Start")     for el1 := range it1 {            if el2, ok := <- it2; !ok {                   t.Error("it2 shorter than it1!", el1)                   return            } else if !reflect.DeepEqual(el1, el2) {                   t.Error("Elements are not equal", el1, el2)            } else {                   t.Log(el1, el2)            }     }     if el2, ok := <- it2; ok {            t.Error("it1 shorter than it2!", el2)     }     t.Log("Stop")}

In our test function TestMap, we define a mapper function literal that is passed to our Map function to perform the transformation. The mapper function returns the length of each string passed to it:

func TestMap(t *testing.T) { mapper := func (i interface{}) interface{} ...