Update ldict-keys.

doc/utils.md

@@ -90,6 +90,12 @@ the dictionary does not contain the key ```k```, an error is raised.
 Sets existing key ```k``` to the new value ```v``` or inserts it if it
 is not already present in the dictionary ```ld```.
 
+    (ldict-keys ld)
+
+* ```ld``` - a ldict instance
+
+Returns the list of keys stored in given dictionary.
+
 ### IO
 
     (import util-io)

src/util-dict.scm

@@ -39,6 +39,7 @@
   
   ldict-remove
   ldict-set
+  
   ldict-keys
   ldict-map
   ldict-filter
@@ -144,8 +145,8 @@
 		     (cons (car pairs) res)))))))
 
  ;; Returns the list of keys stored in given dictionary.
- (define (dict-keys d)
+ (define (ldict-keys ld)
-   (map car d))
+   (map car (ldict-pairs ld)))
 
  ;; Maps dictionary values, the procedure gets key-value pairs if it
  ;; accepts more than one argument. If it accepts a third argument,