在包含地图[int] * somepointer的接口{}上循环

Question

I have to deal with a lot of maps with int keys which contain pointers to different datatypes.

I need a function (and not 10 functions for each map type) to range over those maps and get the maximum and minimum key values.

Answer 1

Use the reflect package to operate on maps with integer keys and arbitrary value types:

func getMaxKey(inout interface{}) int {
    keys := reflect.ValueOf(inout).MapKeys()
    if len(keys) == 0 {
        return 0
    }
    max := keys[0].Int()
    for _, key := range keys[1:] {
        n := key.Int()
        if n > max {
            max = n
        }
    }
    return int(max)
}

Run it on the playground.