undefined method (NoMethodError) ruby

Question

I keep getting the following error message:

text.rb:2:in `<main>': undefined method `choices' for main:Object (NoMethodError)

But I can't seem to understand why my method is "undefined":

puts "Select [1] [2] [3] or [q] to quit"; users_choice = gets.chomp 
choices(users_choice)

def choices (choice)    
   while choice != 'q'      
        case choice

        when '1' 
            puts "you chose one!"

        when '2'
            puts "you chose two!"

        when '3'
            puts "you chose three!"
        end     
   end 
end

Answer 1

This is because you are calling method choices, before defining it. Write the code as below:

puts "Select [1] [2] [3] or [q] to quit"
users_choice = gets.chomp 

def choices (choice)    
  while choice != 'q'      
    case choice
    when '1' 
      break  puts "you chose one!"
    when '2'   
      break puts "you chose two!"
    when '3'
      break  puts "you chose three!"
    end     
  end 
end

choices(users_choice)

I used break, to exit from the while loop. Otherwise it will create an infinite loop.

Answer 2

def main
puts "Select [1] [2] [3] or [q] to quit"; users_choice = gets.chomp
choices(users_choice)
end

def choices (choice)
  while choice != 'q'
    case choice

      when '1'
        puts "you chose one!"
        break
      when '2'
        puts "you chose two!"
        break
      when '3'
        puts "you chose three!"
        break
    end
  end
end

main

The method only needs to be called prior to being executed. Here I wrap the definition in the main method, but only call main after the definition of choices().