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Bug #11115

Updated by nobu (Nobuyoshi Nakada) about 9 years ago

Here's what normally happens when I try to reference a local variable that doesn't exist: 

 ~~~ruby ~~~ 
 def foo 
   bar 
 end 

 foo 
 # => NameError: undefined local variable or method `bar' 
 ~~~ 

 But if I assign bar to "itself", it doesn't raise an error 

 ~~~ruby ~~~ 
 def foo 
   bar = bar 
   bar 
 end 

 foo 
 # => no results 
 ~~~ 

 Looks like `bar` in the second example is being set to `nil`. This doesn't feel very intuitive to me; shouldn't this raise an error? I mean, if you try to assign the non-existent variable 'bar' to anything else, that's how it works: 

 ~~~ruby ~~~ 
 def foo 
   fizz = bar 
 end 

 foo 
 # => NameError: undefined local variable or method `bar' 
 ~~~ 

 Is this a bug, or a feature? 

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