For mm a map of map, turns {:foo {}} to {:foo {:id :foo}} so they key of the outer map is found in the inner one.

Deep merge nested maps. When multiple values are found for a key, the value from the last map has higher priority

This code comes from this gist

Returns the key if it exists in the sorted-map

Note this is not an efficient way

Params: * m the sorted map * n

Returns the key if it exists in the sorted-map

Note this is not an efficient way

Params: * m the sorted map * n

Remove nil values