Currently, Range#=== is an alias of #include?, which works by #each-ing all the values and comparing them to the checked value. It may lead to fascinating inefficiencies, when working with strings or other similar classes (for example, IP class for allowing/disallowing IP ranges). Moreover, it is not consistent with behavior of numerical ranges (which is kinda special case, I guess):
(1...3)===2.5# true - though (1..3).to_a.include?(2.5) is false('a'...'z')==='foo'# false - because ('a'..'z').to_a.include?('foo') is false
As === is heavily used in case and grep, and there is no option to replace it manually with cover? there, maybe it would be reasonable to change the behavior?
To be honest, I could imagine no real cases when include? is preferable for identity check.
I encountered the problem in production code, it was not strings, but specialized IPAddress class, to filter "if IP is in range" -- it was SUDDENLY 0.4 sec on each request to server spent just to (IPAddress.new(from)..IPAddress.new(to)).to_a in "innocently" looking:
Any other specialized enumerable AND comparable value class
Yes, proposed behavior is incompatible with current, but I am not sure it is a bad thing:
(Date.parse('2016-05-01')..Date.today)===DateTime.parse('2016-06-01 12:30')# => false (Date.parse('2016-05-01')..Date.today).cover?(DateTime.parse('2016-06-01 12:30'))# => true # Which is more logical? What you'll intuitively expect here:caseDateTime.parse('2016-06-01 12:30')whenDate.parse('2016-05-01')..Date.today# looks like we SHOULD be here, but...
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