diff -Nur a/lib/websocket/extensions/parser.rb b/lib/websocket/extensions/parser.rb
--- a/lib/websocket/extensions/parser.rb	2023-08-01 10:59:55.411703622 +0800
+++ b/lib/websocket/extensions/parser.rb	2023-08-01 10:59:46.940697645 +0800
@@ -38,7 +38,7 @@
             else
               data = true
             end
-            if data =~ NUMBER
+            if data != true and data =~ NUMBER
               data = data =~ /\./ ? data.to_f : data.to_i(10)
             end