diff --git a/lib/kiss/kiss_abstract.rb b/lib/kiss/kiss_abstract.rb
index ede0cc0cc3a7b0d6399ec5c9620cfd5a45bc40ca..7fc6a23bd01fea0df23f75a206564442af96fb50 100644
--- a/lib/kiss/kiss_abstract.rb
+++ b/lib/kiss/kiss_abstract.rb
@@ -18,10 +18,10 @@ module Kiss
             while frame[0] == DATA_FRAME
                 frame.shift
             end
-            while frame[0]&.chr == ' '
+            while frame[0] and frame[0].chr == ' '
                 frame.shift
             end
-            while frame[-1]&.chr == ' '
+            while frame[-1] and frame[-1].chr == ' '
                 frame.pop
             end
             frame