6 files changed, 20 insertions, 15 deletions
diff --git a/lib/zambyte/meta/180.scm b/lib/zambyte/meta/180.scm
index 71ee1a8..de9e2dd 100644
--- a/lib/zambyte/meta/180.scm
+++ b/lib/zambyte/meta/180.scm
@@ -29,9 +29,10 @@
 	(get-output-string port))))
 
   (define (json-object-ref json key)
-    (or (and-let* ((pair (assoc (string->symbol key) json)))
-	  (cdr pair))
-	((json-key-not-found))))
+    (let ((pair (assoc (string->symbol key) json)))
+      (if pair
+	  (cdr pair)
+	  ((json-key-not-found)))))
 
   (define json-list-ref vector-ref)
   (define json-list-length vector-length)
diff --git a/lib/zambyte/meta/chibi.scm b/lib/zambyte/meta/chibi.scm
index fc8e942..286240d 100644
--- a/lib/zambyte/meta/chibi.scm
+++ b/lib/zambyte/meta/chibi.scm
@@ -23,9 +23,10 @@
   ;; string->json already defined in chibi json
 
   (define (json-object-ref json key)
-    (or (and-let* ((pair (assoc (string->symbol key) json)))
-	  (cdr pair))
-	((json-key-not-found))))
+    (let ((pair (assoc (string->symbol key) json)))
+      (if pair
+	  (cdr pair)
+	  ((json-key-not-found)))))
 
   (define json-list-ref vector-ref)
   (define json-list-length vector-length)
diff --git a/lib/zambyte/meta/gauche.scm b/lib/zambyte/meta/gauche.scm
index 3ab2062..34a755a 100644
--- a/lib/zambyte/meta/gauche.scm
+++ b/lib/zambyte/meta/gauche.scm
@@ -31,8 +31,10 @@
   (define json->string construct-json-string)
 
   (define (json-object-ref json key)
-    (or (assoc-ref json key)
-	((json-key-not-found))))
+    (let ((pair (assoc (string->symbol key) json)))
+      (if pair
+	  (cdr pair)
+	  ((json-key-not-found)))))
 
   (define json-list-ref vector-ref)
   (define json-list-length vector-length)
diff --git a/lib/zambyte/meta/gerbil.scm b/lib/zambyte/meta/gerbil.scm
index 8d545ef..173ef71 100644
--- a/lib/zambyte/meta/gerbil.scm
+++ b/lib/zambyte/meta/gerbil.scm
@@ -19,8 +19,8 @@
   (define json->string json-object->string)
 
   (define (json-object-ref json key)
-    (or (and (json-object-contains-key? json key)
-	     (hash-table-ref json key))
+    (if (json-object-contains-key? json key)
+	(hash-table-ref json key)
 	((json-key-not-found))))
 
   (define json-list-ref list-ref)
diff --git a/lib/zambyte/meta/macduffie.scm b/lib/zambyte/meta/macduffie.scm
index 8a42183..288192b 100644
--- a/lib/zambyte/meta/macduffie.scm
+++ b/lib/zambyte/meta/macduffie.scm
@@ -15,8 +15,8 @@
   (define json->string json-write-string)
 
   (define (json-object-ref json key)
-    (or (and (hash-table-exists? json key)
-	     (hash-table-ref json key))
+    (if (hash-table-exists? json key)
+	(hash-table-ref json key)
 	((json-key-not-found))))
 
   (define json-list-ref list-ref)
diff --git a/lib/zambyte/meta/sagittarius.scm b/lib/zambyte/meta/sagittarius.scm
index 97deb0b..e8d82ae 100644
--- a/lib/zambyte/meta/sagittarius.scm
+++ b/lib/zambyte/meta/sagittarius.scm
@@ -42,9 +42,10 @@
 	(get-output-string port))))
 
   (define (json-object-ref json key)
-    (or (and-let* ((pair (assoc key (json-object->alist json))))
-	  (cdr pair))
-	((json-key-not-found))))
+    (let ((pair (assoc key (json-object->alist json))))
+      (if pair
+	  (cdr pair)
+	  ((json-key-not-found)))))
 
   (define (json-list-ref json index)
     (list-ref (json-list->list json) index))