How to check if a number is included in a range (in one statement)?

ruby-on-rails ruby ruby-on-rails-3 numbers range
Backo picture Backo · Jul 30, 2011 · Viewed 65k times · Source

I am using Ruby on Rails 3.0.9 and I would like to check if a number is included in a range. That is, if I have a variable number = 5 I would like to check 1 <= number <= 10 and retrieve a boolean value if the number value is included in that range.

I can do that like this:

number >= 1 && number <= 10

but I would like to do that in one statement. How can I do that?

Answer

Mario Uher picture Mario Uher · Jul 30, 2011

(1..10).include?(number) is the trick.

Btw: If you want to validate a number using ActiveModel::Validations, you can even do:

validates_inclusion_of :number, :in => 1..10

read here about validates_inclusion_of

or the Rails 3+ way:

validates :number, :inclusion => 1..10

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