# Save the edge in base
	# From and to nodes will be created.
	#
	#     var client = new Neo4jClient("http://neo4j:7474")
	#
	#     var andres = new NeoNode
	#     var kate = new NeoNode
	#     var edge = new NeoEdge(andres, "LOVES", kate)
	#     client.save_edge(edge)
	#     assert andres.is_linked
	#     assert kate.is_linked
	#     assert edge.is_linked
	fun save_edge(edge: NeoEdge): Bool do
		if edge.is_linked then return true
		edge.neo = self
		edge.from.out_edges.add edge
		edge.to.in_edges.add edge
		var batch = new NeoBatch(self)
		batch.save_edge(edge)
		var errors = batch.execute
		if not errors.is_empty then
			errors.add_all errors
			return false
		end
		local_edges[edge.url.to_s] = edge
		return true
	end