Question

Is it possible to create ranges in ruby that exclude one or both of the endpoints. So handling the concept in mathematics of open and closed interval boundaries?

For example, can I define a range from 1.0 to 10.0 that excludes 1.0

Say (with pseudo-ruby)

range = [1.0...10.0)

range === 1.0
=> false

range === 10.0
=> true

Answer 1

you can exclude rightmost element of the range with .... See example below

(1..10).to_a # an array of numbers from 1 to 10 - [1, 2, 3, 4, 5, 6, 7, 8, 9, 10]

(1...10).to_a # an array of numbers from 1 to 9 - [1, 2, 3, 4, 5, 6, 7, 8, 9]