case KW_THIS:
consumeLookAhead();
return conclude(srOf(lastLexElement(), new ExpThis()));
case KW_SUPER:
consumeLookAhead();
return conclude(srOf(lastLexElement(), new ExpSuper()));
case KW_NULL:
consumeLookAhead();
return conclude(srOf(lastLexElement(), new ExpNull()));
case DOLLAR:
consumeLookAhead();