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Is there a simple way to evaluate whether an integer is within that range using the (2..100) syntax.

For example, say I wanted to evaluate as true if my integer x = 100, and my range is (0..200), I'm just looking for the simple, concise ruby-way of doing this.

JP Silvashy
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5 Answers5

154

There are many ways of doing the same things in Ruby. You can check if value is in the range by use of following methods,

14.between?(10,20) # true

(10..20).member?(14) # true

(10..20).include?(14) # true

But, I would suggest using between? rather than member? or include?

All number literals denote inclusive ranges. You can find more about it on Ruby in Rails.

Akshay Mohite
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  • Also covered in the [Ruby community style guide](https://github.com/bbatsov/ruby-style-guide/commit/1b8c788c836f00507056eba21d4b9ca8078eec3e). – Dennis Feb 21 '14 at 18:37
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You can use the === operator:

(1..10) === 1 #=> true
(1..10) === 100 #=> false
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Rudy Matela
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    Just note, when using this solution I found that You need to be aware of order in which is condition written `1 === (1..10)` will produce false – Kovo Nov 04 '18 at 23:40
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you can use the member? method of the range to test this 

 (1..10).member?(1)   => true
 (1..10).member?(100) => false
Nikolaus Gradwohl
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(2..100).include?(5) #=> true
(2..100).include?(200) #=> false

Note that 2..0 is an empty range, so (2..0).include?(x) will return false for all values of x.

sepp2k
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0

have a look at this question: Determining if a variable is within range?

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Raoul Duke
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