Merge branch 'dev' of https://github.com/terminusdb/terminus-client into dev

Author: Francesca-Bit

lib/woql.js

@@ -619,11 +619,11 @@ WOQLQuery.prototype.getInstanceMeta = function(url){
 
 WOQLQuery.prototype.simpleGraphQuery = function(){
 	return this.and(
-	    WOQL.triple("v:Source", "rdf:type", "v:Source_Class"),
+	    WOQL.triple("v:Source", "v:Edge", "v:Target"),
+	    WOQL.isa("v:Source", "v:Source_Class"),
 	    WOQL.sub("v:Source_Class", "tcs:Document"),
-	    WOQL.triple("v:Target", "rdf:type", "v:Target_Class"),
+	    WOQL.isa("v:Target", "v:Target_Class"),
 	    WOQL.sub("v:Target_Class", "tcs:Document"),
-	    WOQL.triple("v:Source", "v:Edge", "v:Target"),
 	    WOQL.opt().triple("v:Source", "rdfs:label", "v:Source_Label"),
 	    WOQL.opt().triple("v:Source", "rdfs:comment", "v:Source_Comment"),
 	    WOQL.opt().quad("v:Source_Class", "rdfs:label", "v:Source_Type", "db:schema"),