PatternComprehension = '[', [SP], [Variable, [SP], '=', [SP]], RelationshipsPattern, [SP], [Where, [SP]], '|', [SP], Expression, [SP], ']' ;
Variable = SymbolicName ;
RelationshipsPattern = NodePattern, { [SP], PatternElementChain }- ;
PatternElementChain = RelationshipPattern, [SP], NodePattern ;
Where = (W,H,E,R,E), SP, Expression ;