c_gtk_tree_store_insert_before

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)
void function(GtkTreeStore* treeStore, GtkTreeIter* iter, GtkTreeIter* parent, GtkTreeIter* sibling) c_gtk_tree_store_insert_before;

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