WARNING: This function is slow. Only use it for debugging and/or testing purposes.
Checks if the given iter is a valid iter for this #GtkTreeStore.
A #GtkTreeIter.
%TRUE if the iter is valid, %FALSE if the iter is invalid.
See Implementation
WARNING: This function is slow. Only use it for debugging and/or testing purposes.
Checks if the given iter is a valid iter for this #GtkTreeStore.