diff --git a/lib/json_logic/operation.rb b/lib/json_logic/operation.rb
index 5cec5b6..d1e3d66 100644
--- a/lib/json_logic/operation.rb
+++ b/lib/json_logic/operation.rb
@@ -79,10 +79,16 @@ class Operation
         end
       end,
       'if' => ->(v, d) {
-        v.each_slice(2) do |condition, value|
-          return condition if value.nil?
-          return value if condition.truthy?
+        v.each_slice(2) do |condition_and_value|
+          # If this slice a single value? It's an else value only.
+          if condition_and_value.size == 1
+            return condition_and_value.first
+          else
+            condition, value = condition_and_value
+            return value if condition.truthy?
+          end
         end
+        nil
       },
       '=='    => ->(v, d) { v[0].to_s == v[1].to_s },
       '==='   => ->(v, d) { v[0] == v[1] },
diff --git a/test/json_logic_test.rb b/test/json_logic_test.rb
index 2f76271..6efc7c4 100644
--- a/test/json_logic_test.rb
+++ b/test/json_logic_test.rb
@@ -8,7 +8,7 @@
 
 class JSONLogicTest < Minitest::Test
   test_suite_url = 'http://jsonlogic.com/tests.json'
-  tests = JSON.parse(open(test_suite_url).read)
+  tests = JSON.parse(URI.open(test_suite_url).read)
   count = 1
   tests.each do |pattern|
     next unless pattern.is_a?(Array)