Ruby » Ruby master

Feature #12113

Updated by nobu (Nobuyoshi Nakada) over 8 years ago

~~~ruby ~~~ 
 def some_func 
   puts '12' 
 end 

 class Klass < Delegator 
   def initialize(obj) 
     @obj = obj 
   end 

   def __getobj__ 
     @obj 
   end 

   def func 
     some_func #=> /home/oleg/.rbenv/versions/2.3.0/lib64/ruby/2.3.0/delegate.rb:85:in `instance_method': undefined method `some_func' for module `Kernel' (NameError) 
   end 
 end 

 Klass.new(0).func 
 ~~~ 
 Delegator uses Kernel.instance_method (https://github.com/ruby/ruby/blob/trunk/lib/delegate.rb#L85) but: 

 ~~~ruby ~~~ 
 ::Kernel.respond_to?(:some_func, true) #=> true 
 ::Kernel.instance_method(:some_func)     #=> `instance_method': undefined method `some_func' for module `Kernel' (NameError) 
 ::Kernel.method(:some_func)              #=> #<Method: Module(Object)#some_func> 
 ~~~ 

 I think there should be `Kernel.method` Kernel.method instead of `instance_method` instance_method (in Delegator). Otherwise you get `respond_to?` respond_to? == `true`, true, but cannot use this method and get an error.

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