Returns a node list containing all the nodes from nodelist that are not PIs. The order of nodes in the node list is preserved.
(define (node-list-filter-out-pis nodelist) ;; Returns the nodelist with all PIs removed (let loop ((result (empty-node-list)) (nl nodelist)) (if (node-list-empty? nl) result (if (equal? (node-property 'class-name (node-list-first nl)) 'pi) (loop result (node-list-rest nl)) (loop (node-list result (node-list-first nl)) (node-list-rest nl))))))