insertNode
Inserts a key/value pair into a #GTree.
If the given key already exists in the #GTree its corresponding value is set to the new value. If you supplied a @value_destroy_func when creating the #GTree, the old value is freed using that function. If you supplied a @key_destroy_func when creating the #GTree, the passed key is freed using that function.
The tree is automatically 'balanced' as new key/value pairs are added, so that the distance from the root to every leaf is as small as possible. The cost of maintaining a balanced tree while inserting new key/value result in a O(n log(n)) operation where most of the other operations are O(log(n)).
Return
the inserted (or set) node or null if insertion would overflow the tree node counter.
Since
2.68
Parameters
the key to insert
the value corresponding to the key