Add json-object-contains-key?, json-list-length, and json-key-not-found.

Update README accordingly and with add examples.

1 files changed, 11 insertions, 5 deletions

diff --git a/lib/zambyte/meta/gerbil.scm b/lib/zambyte/meta/gerbil.scm
index 00f7b0e..8d545ef 100644
--- a/lib/zambyte/meta/gerbil.scm
+++ b/lib/zambyte/meta/gerbil.scm
@@ -1,23 +1,29 @@
 (import (std text json)
 	(scheme hash-table))
 (begin
-  (define string->json string->json-object)
-  (define json->string json-object->string)
-
   (define (json-object . pairs)
     (alist->hash-table pairs equal?))
 
   (define json-list list)
-  (define json-null #!void)
+  (define json-null (if #f #f))
   (define json-object? hash-table?)
   (define json-list? list?)
 
   (define (json-null? obj)
     (eq? obj json-null))
 
+  (define (json-object-contains-key? json key)
+    (hash-table-contains? json key))
+
+  (define string->json string->json-object)
+  (define json->string json-object->string)
+
   (define (json-object-ref json key)
-    (hash-table-ref json (string->symbol key)))
+    (or (and (json-object-contains-key? json key)
+	     (hash-table-ref json key))
+	((json-key-not-found))))
 
   (define json-list-ref list-ref)
+  (define json-list-length length)
   (define json-object->alist hash-table->alist)
   (define json-list->list values))