I have a nested (not embedded) struct for which some of field types are arrays.
How can I check if an instance of this struct is empty? (not using iteration!!)
Note that there can't use StructIns == (Struct{})
or by an empty instance! This code have this error:
invalid operation: user == model.User literal (struct containing model.Configs cannot be compared)
user.Configs.TspConfigs:
type TspConfigs struct {
Flights []Flights `form:"flights" json:"flights"`
Tours []Tours `form:"tours" json:"tours"`
Insurances []Insurances`form:"insurances" json:"insurances"`
Hotels []Hotels `form:"hotels" json:"hotels"`
}
Those are slices, not arrays. It's important to emphasize as arrays are comparable but slices are not. See Spec: Comparision operators. And since slices are not comparable, structs composed of them (structs with fields having slice types) are also not comparable.
You may use reflect.DeepEqual()
for this. Example:
type Foo struct {
A []int
B []string
}
f := Foo{}
fmt.Println("Zero:", reflect.DeepEqual(f, Foo{}))
f.A = []int{1}
fmt.Println("Zero:", reflect.DeepEqual(f, Foo{}))
Output (try it on the Go Playground):
Zero: true
Zero: false