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Ruby Ruby Loops Build a Simple Contact List Part 1: Asking Questions

Thomas Salai
Thomas Salai
4,389 Points

Why do we check number in as a String ?

Why do we check here if kind == as a String in double quote! ? Do we check here answer(which is from uswer input) is Numeric Type or NOT ?

def ask(question,kind="string")
  print question + " "
  answer = gets.chomp
  answer = answer.to_i if kind == "number"
  return answer
end

answer = ask("What is your name?")
puts answer
answer = answer.to_i if kind == "number"
this line and 
answer = answer.to_i if kind == "number"
this line are same ?
answer = answer.to_i if answer.is_a?(Numeric)

this comparison with String value "number" make me confusions. Can anybody explain me here why we do this and how Ruby interpret the comparison == "number".

many thanks in advance.

Thomas

2 Answers

ellie adam
ellie adam
26,376 Points

hi there, It is always a question why we check number in as a String ?

For example when i am checking numeric or not am expecting as below results

"34" =>  true
34 => true
"34sdfds" => it should return false
34.90 =>  false
"34.90" => false

This is very helpful article; http://mentalized.net/journal/2011/04/14/ruby-how-to-check-if-a-string-is-numeric/

happy coding :)

rowend rowend
rowend rowend
2,926 Points

Well, let me say this: The ask method get 2 arguments. The first argument question is not optional. The second argument kind is optional and have a default value 'string'. This means you can call your method like:

ask('what is your name?') in this case the method will no do the integer conversion.
ask('waht is your age?', 'number') in this case the method will do the integer conversion.

I hope this help you.