Silence method redefinition warning

Library/Homebrew/debrew/irb.rb

@@ -3,12 +3,13 @@ require 'irb'
 module IRB
   @setup_done = false
 
-  def IRB.parse_opts
+  extend Module.new {
+    def parse_opts
     end
 
-  def IRB.start_within(binding)
+    def start_within(binding)
       unless @setup_done
-      IRB.setup(nil)
+        setup(nil)
         @setup_done = true
       end
 
@@ -30,4 +31,5 @@ module IRB
         irb_at_exit
       end
     end
+  }
 end