if true the given value will replace the first item in the tree that is equivalent (That is greater-than and less-than are both false) to value. This is useful in cases where opCmp and opEquals for T type have different meanings. For example, if the element type is a circle that has a position and a color, the circle could implement opCmp to sort by color, and calling insert with overwrite set to true would allow you to update the position of the circle with a certain color in the tree.
the number of values added.
Inserts the given value(s) into the tree.
This is not a stable insert. You will get strange results if you insert into a tree while iterating over it.