From: "David A. Black" <dblack@...>
Date: 2010-05-17T23:53:50+09:00
Subject: Re: Range on strings.

On Mon, 17 May 2010, Rick DeNatale wrote:

> On Mon, May 17, 2010 at 8:29 AM, David A. Black <dblack@rubypal.com> wrote:
>> Hi --
>>
>> On Fri, 14 May 2010, Vikrant Chaudhary wrote:
>>
>>> Hi,
>>> If I do -
>>>
>>> ('A'..'Z').include?('AA')
>>>
>>> It returns "true", while
>>>
>>> ('A'..'Z').to_a.include?('AA')
>>>
>>> (of course) returns "false". Is it intentional or possibly a bug?
>>> I'm using ruby 1.8.7 (2010-01-10 patchlevel 249) [x86_64-linux] on
>>> Ubuntu 10.04 x64
>>
>> As per the other answers, it's because ('A'..'Z').to_a is an array of
>> discrete values, whereas ('A'..'Z') is a range with a start and end.
>> I'll just add that in Ruby 1.9, things have changed so that include?
>> on a range is, I think, the same as .to_a.include?
>
> Not exactly.  Range#include? for Ruby 1.9 has a few special cases.

[snip]

Thanks. I was being lazy, so I'm glad for the further info :-)


David

-- 
David A. Black, Senior Developer, Cyrus Innovation Inc.

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