* management of their lifetimes must be completely managed by API users.
*
* For API usage, in general,
- * - any function _modifying_ the the tree or tags (inserting or deleting
+ * - any function _modifying_ the tree or tags (inserting or deleting
* items, setting or clearing tags must exclude other modifications, and
* exclude any functions reading the tree.
- * - any function _reading_ the the tree or tags (looking up items or tags,
+ * - any function _reading_ the tree or tags (looking up items or tags,
* gang lookups) must exclude modifications to the tree, but may occur
* concurrently with other readers.
*