It is a bit like neo4j's cypher, (2) is an edge, like a circle, [2] is a label, like in a property graph. (Alice)--[loves]-->(Bob) (loves)--[type]-->(Pr

It is a bit like neo4j's cypher, (2) is an edge, like a circle, [2] is a label, like in a property graph. (Alice)--[loves]-->(Bob) (loves)--[type]-->(Property) --[domain]-->(Human) --[range]-->(Human) (type)--... Sort of like that, cypher does not support this type of expression though.