How do you return a boolean value for a regexp scan of an integer?

I'm looking through my object attributes开发者_JS百科 for culprits that are not :

^[1-3]{3}$

What is the method used to scan integers for regexp?

---

Some examples:

124.to_s.match(/^[1-3]{3}$/)
=> nil
123.to_s.match(/^[1-3]{3}$/)
=>#<MatchData "123">

Since nil is considered as false, you have your boolean.

Ex:

 "no yo" if 124.to_s.match(/^[1-3]{3}$/)
 => nil
 "yo!" if 123.to_s.match(/^[1-3]{3}$/)
 => "yo!"

---

You may use also one of the following:

def is_pure_integer?(i)
  i.to_i.to_s == i.to_s
end

or

'132' =~ /^\d+$/ ? true : false