Creating a flat array from the map entries in Go

What is the shortest (and idiomatic) way to create an array from the keys and values of a map w/o compromising on time complexity too much?

For instance, from the following map:

map[string]string { "1":"a", "2":"b" }

I need to create the following array:

[]string{"1","a", "2","b"}

I can do this in Scala with following:

val myMap = Map("1" -> "a", "2" -> "b")
myMap.keySet ++ myMap.values

Thank you.

Solution

Simplest way would be to just iterate the map, since in Go the syntax would allow direct access to keys and values and dump them into the array.

m := map[string]string { "1":"a", "2":"b" }
arr := []string{}
for k, v := range m { 
   arr = append(arr, k, v)
}

One caveat here: In Go, map iteration order is randomized, as you can see here, under "Iteration Order":

So if you want your resulting array to have a particular ordering, you should first dump the keys and order (as shown in that same blog entry).

Playground (without the sorting part):