aexpr_new()instantiates a newaexprnode.aexpr_type()checks if the node is aaexprnode.aexpr_<child>_get()returns the<child>node ofaexpr.aexpr_<child>_set()sets the new<child>and deletes the old<child>.aexpr_<child>_rep()sets the new<child>and returns the old<child>.