code: function capture( previousExpr, detection ) {
  
        // extract meaning from the detection      
        var capturing = !!detection[CAPTURING_INDEX];
  
        if (!capturing)          
           return previousExpr; // don't wrap at all, return given expr as-is      
        
        return lazyIntersection(previousExpr, head);
              
     }
docs: Expression for $, returns the evaluator function