Added space separated string to IntSlice conversion

cast_test.go

@@ -987,10 +987,12 @@ func TestToIntSliceE(t *testing.T) {
 		{[]interface{}{1.2, 3.2}, []int{1, 3}, false},
 		{[]string{"2", "3"}, []int{2, 3}, false},
 		{[2]string{"2", "3"}, []int{2, 3}, false},
+		{"2 3", []int{2, 3}, false},
 		// errors
 		{nil, nil, true},
 		{testing.T{}, nil, true},
 		{[]string{"foo", "bar"}, nil, true},
+		{"2 a", []int{}, true},
 	}
 
 	for i, test := range tests {

caste.go

@@ -1151,6 +1151,8 @@ func ToIntSliceE(i interface{}) ([]int, error) {
 	switch v := i.(type) {
 	case []int:
 		return v, nil
+	case string:
+		return ToIntSliceE(strings.Fields(v))
 	}
 
 	kind := reflect.TypeOf(i).Kind()