Finding and filtering pairs.

src/util-bst.scm

@@ -26,8 +26,8 @@
   
   bst-balance
 
-  ;; bst-find-pair
-  ;; bst-filter-pairs
+  bst-find-pair
+  bst-filter-pairs
 
   ;; bst-map-list
   ;; bst-map-dict
@@ -240,8 +240,8 @@
    ("Returns all the keys contained in given dictionary.")
    (let ((res '()))
      (bst-iter-kv bst
-		  (lambda (k v)
-		    (set! res (cons k res))))
+		  (lambda (kv)
+		    (set! res (cons (car kv) res))))
      (reverse res)))
 
  ;; Converts BST to KVV
@@ -295,6 +295,25 @@
    (kvv->bst
     (bst->kvv bst)))
 
+ (define/doc (bst-find-pair bst pred?)
+   ("Finds pair by predicate that accepts both key and value.")
+   (call/cc
+    (lambda (cc)
+      (bst-iter-kv bst
+		   (lambda (kv)
+		     (when (pred? (car kv) (cdr kv))
+		       (cc kv))))
+      #f)))
+
+ (define/doc (bst-filter-pairs bst pred?)
+   ("Returns a list of key-value pairs matching predicate.")
+   (let ((res '()))
+     (bst-iter-kv bst
+		  (lambda (kv)
+		    (when (pred? (car kv) (cdr kv))
+		      (set! res (cons kv res)))))
+     res))
+
  ;; Module self-tests
  (define (util-bst-tests!)
    (run-tests