Element: treenode.exec { }
Element: treenode.exec { }callback
A callback procedure invoked if the return key is pressed when treenode is selected.
This procedure is a class procedure so can only be set via a treenode class name not via a treenode instance name, e.g. if a treenode "mynode" is of class "database_t", then database_t.exec can be set, but mynode.exec may not.
<treenode>.exec(<treenode>)