Is there any difference when defining a range with two dots and three dots in ruby?

Question

I tried this in my rails console.

2.0.0-p481 :012 > a = 1
 => 1 
2.0.0-p481 :013 > z = 26
 => 26 
2.0.0-p481 :014 > a..z
 => 1..26 
2.0.0-p481 :015 > a...z
 => 1...26

What is the difference between the two?

http://stackoverflow.com/questions/9690801/difference-between-double-dot-and-triple-dot-in-range-generation — Mircea, Mar 05 '15 at 06:39

score 2 · Accepted Answer · answered Mar 05 '15 at 06:41

2

A quick check:

(1..3).to_a
# => [1, 2, 3] 
(1...3).to_a
# => [1, 2]

Its evident ... does not include the last value i.e. its the range till n-1.

answered Mar 05 '15 at 06:41

shivam

score 0 · Answer 2 · answered Mar 05 '15 at 06:42

0

Yes, the version with two dots includes the last element, the one with three dots does not:

(1..4).to_a
#=> [1, 2, 3, 4]

(1...4).to_a
#=> [1, 2, 3]

answered Mar 05 '15 at 06:42

spickermann

2 Answers2