moduleArelmoduleNodes#### Class that represents a join source## http://www.sqlite.org/syntaxdiagrams.html#join-sourceclassJoinSource<Arel::Nodes::Binarydefinitializesingle_source,joinop=[]superenddefinitialize_copyothersuper@left=@left.cloneif@left@right=@right.cloneif@rightendendendend