29

For this piece of code:

class myBaseClass
  def funcTest()
    puts "baseClass"
  end
end
myBaseClass.new.funcTest

I am getting an error:

NameError: undefined local variable or method `myBaseClass' for main:Object
from c:/Users/Yurt/Documents/ruby/polymorphismTest.rb:9
from (irb):145:in `eval'
from (irb):145
from c:/Ruby192/bin/irb:12:in `<main>'
irb(main):152:0> x=myBaseClass.new

When I tryx=myBaseClass.new, I get:

NameError: undefined local variable or method `myBaseClass' for main:Object from (irb):152

Has someone already encountered this problem? I don't think my code can be wrong.

edgerunner
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S4M
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4 Answers4

64

In ruby, all constants including class names must begin with a capital letter. myBaseClass would be interpreted as an undefined local variable. MyBaseClass would work properly.

edgerunner
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    Interestingly, you're allowed to do this: `class Foo; end; f = Foo; f.new` – jtbandes Jun 26 '11 at 20:32
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    That's because a class is an object and can be assigned to a variable. You can define and use a class without ever assigning it to a constant: `f=Class.new; f.new` gives you an instance of the unnamed class residing in the local variable `f` – edgerunner Jun 26 '11 at 21:31
6

Your class name should start with a capital, working code below

class MyBaseClass
  def funcTest()
   puts "baseClass"
 end
end



MyBaseClass.new.funcTest
mu is too short
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Steve
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3

Your code is wrong. Classnames must start with an uppercase in Ruby.

class MyBaseClass

fixes it.

What I don't get is how you don't get a clear error message like I do.

Bruno Rohée
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    I am running ruby 1.9.2, on windows, gotten from the oneclick installer. Out of curiosity, what is the error message I should be getting? – S4M Jun 26 '11 at 20:25
  • my 1.9.2 p180 ( ubuntu) says: SyntaxError: (irb):1: class/module name must be CONSTANT – steenslag Jun 26 '11 at 20:57
0

Code working

class MyBaseClass
  def funcTest()
   puts "baseClass"
 end
end
MyBaseClass.new.funcTest
john mwadime
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  • As it’s currently written, your answer is unclear. Please [edit] to add additional details that will help others understand how this addresses the question asked. You can find more information on how to write good answers [in the help center](/help/how-to-answer). – Community May 18 '22 at 12:32