{"ast_node_type":"other","tokens":[{"end":61,"kind":"keyword","start":0,"text":"self.nodes[source.0].first_edge[OUTGOING.repr]"}]}
        self.nodes[source.0].first_edge[OUTGOING.repr] = idx;
        // adjust the firsts for each node target be the next object.
        self.nodes[target.0].first_edge[INCOMING.repr] = idx;