创建通用函数以从地图提取值

Question

Go beginner here, I am trying to create a generic routine to extract the values from a map, I have this right now:

func getValues(m map[interface{}]interface{}) []interface{} {

    v := make([]interface{}, 0, len(m))

    for _, value := range m {
        v = append(v, value)
    }

    return v
}

and I called it like so:

nearby := make(map[string]Nearby)
values := getValues(nearby)

but I get this error:

cannot use nearby (type map[string]Nearby) as type map[interface {}]interface {} in argument to getValues

Answer 1

It's usually best to just write the type specific code. To answer your question though, use the reflect package:

func getValues(m interface{}) []interface{} {
    v := reflect.ValueOf(m)

    result := make([]interface{}, 0, v.Len())

    for _, k := range v.MapKeys() {
        result = append(result, v.MapIndex(k).Interface())
    }
    return result
}