Undefined Local Variable or Method

Ruby
#1

Today, I started to try to learn ruby. When I went to make my first
method, I kept receiving an error “undefined local variable or method.”

I tried looking up how to make methods in Ruby online, so that I would
be sure its not my own fault. I copy pasted several examples into my
ide, all of which returned the same error.

I made a simple method (below) and I get the same error: class:TEST’:
undefined local variable or method `greeter’ for TEST:Class (NameError)

class TEST

def greeter()
puts ‘Hi’
end
greeter

end

The built in ruby methods work fine. Is there something wrong with what
I’m doing?

#2

Hi Slipper Spe,

You should put “greeter” outside the class TEST. You cannot call a
method
inside a class.

Regards,
Yuanhang.

#3

Ahhh, I see. Earlier, I tried putting it outside, but below the class.
Putting it above works.

Thank you good sir, you helped me a lot :slight_smile:

#4

Wow, this amazes me. Thank you, Abinoam Jr.

Yuanhang Zheng.

#5

Hi Yuanhang Zheng,

That’s right, but I would add that “You cannot call THIS method (the
way you’re doing)”.

But, the code inside the class has not such limitations in Ruby.
Just don’t abuse it, or your code will be a mess!

class Test

def greeter()

Here, self is an instance of the Test class

puts 'Hi, from Test#greeter'

end

def self.method_defined_on_Test
puts “Hello, from Test.method_defined_on_Test”
end

Here, self is the Test class itself

The three bellow are the same

Test.method_defined_on_Test
self.method_defined_on_Test
method_defined_on_Test

Here on the Test instance

test = Test.new
test.greeter

puts “You can do anything here, although not recommended!”

end

Abinoam Jr.