c_gtk_tree_model_iter_nth_child

Undocumented in source but is binding to C. You might be able to learn more by searching the web for its name.
__gshared extern (C)
int function(GtkTreeModel* treeModel, GtkTreeIter* iter, GtkTreeIter* parent, int n) c_gtk_tree_model_iter_nth_child;

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