xtk::bindings should be a collection of bindings for widgets. At the moment there is only one binding, which provide a search function for the ttk::combobox. It shows only the matched values in the dropdown list, which starts with the content of the entry field.
package require xtk::bindings ?0.1?
Version 0.1: [http://download.lima-city.de/lifax/xtk_bindings-0.1.zip%|%xtk_bindings-0.1.zip%|%]
You can test it with TkTest.