From: "David A. Black" <dblack@...>
Date: 2008-07-03T01:34:26+09:00
Subject: Re: Ranges and Enumerable problems

Hi --

On Thu, 3 Jul 2008, Glen Holcomb wrote:

> On Wed, Jul 2, 2008 at 9:12 AM, Robert Klemme <shortcutter@googlemail.com>
> wrote:
>
>> 2008/7/2 Glen Holcomb <damnbigman@gmail.com>:
>>> Okay so when I play with "!".."~" wrong things happen.
>>>
>>> ("!".."~").include?("W")
>>> true
>>>
>>> ("!.."~").include?(" ")
>>> false
>>>
>>> so far so good, however.
>>>
>>> ("!".."~").each do |c|
>>> puts c
>>> end
>>>
>>> !
>>> "
>>> #
>>> $
>>> %
>>> &
>>> '
>>> (
>>> )
>>> *
>>> +
>>> ,
>>> -
>>> .
>>> /
>>> 0
>>> 1
>>> 2
>>> 3
>>> 4
>>> 5
>>> 6
>>> 7
>>> 8
>>> 9
>>> => "!".."~"
>>>
>>> This is wrong!
>>>
>>> ("!".."~").last
>>> => "~"
>>>
>>> This is also right.
>>>
>>> It looks to me like a problem with the Enumerable mixin but I guess the
>>> question is why?
>>
>> Note this
>>
>> irb(main):003:0> "9".succ
>> => "10"
>>
>> Try this instead:
>>
>> (?!..?~).each {|c| p c.chr}
>>
>> irb(main):008:0> (?!..?~).include? ?\
>> => false
>>
> Thanks Robert,
>
> That is interesting.  I wonder why it doesn't work as you would expect.  The
> range object seems to be correct (at least through limited include? testing)
> however it returns incomplete info whenever you use an Enumerable method or
> a method that appears to use an Enumerable method.

In 1.9 you get this:

>> ('!'..'~').to_a
=> ["!", "\"", "#", "$", "%", "&", "'", "(", ")", "*", "+", ",", "-",
".", "/", "0", "1", "2", "3", "4", "5", "6", "7", "8", "9", ":", ";",
"<", "=", ">", "?", "@", "A", "B", "C", "D", "E", "F", "G", "H", "I",
"J", "K", "L", "M", "N", "O", "P", "Q", "R", "S", "T", "U", "V", "W",
"X", "Y", "Z", "[", "\\", "]", "^", "_", "`", "a", "b", "c", "d", "e",
"f", "g", "h", "i", "j", "k", "l", "m", "n", "o", "p", "q", "r", "s",
"t", "u", "v", "w", "x", "y", "z", "{", "|", "}", "~"]


David

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