1 files changed, 1 insertions, 1 deletions
diff --git a/mrblib/string.rb b/mrblib/string.rb
index f91b5a23c..4c6114ecb 100644
--- a/mrblib/string.rb
+++ b/mrblib/string.rb
@@ -133,7 +133,7 @@ class String
     if args.length == 2 && block
       block = nil
     end
-    if !block
+    unless block
       replace = replace.to_str
     end
     result = []