:& buildGr context deg' deg delEdge delEdges delNode delNodes edges emap empty equal gelem gmap indeg' indeg inn' inn insEdge insEdges insNode insNodes isEmpty lab' lab labEdges labNode' labNodes labUEdges labUNodes lpre' lpre lsuc' lsuc match matchAny mkGraph mkUGraph neighbors' neighbors newNodes nmap noNodes node' nodeRange nodes out' out outdeg' outdeg pre' pre showGraph suc' suc ufold