[#393742] Getting the class of an object. — Ralph Shnelvar <ralphs@...32.com>

Consider;

14 messages 2012/03/06

[#393815] arcadia IDE requires tcl/tk and ruby-tk — Thufir Hawat <hawat.thufir@...>

which or where tcl and tk does arcadia require? Is this a gem which I

13 messages 2012/03/13

[#393952] What’s the best way to check if a feature/class has been loaded? — Nikolai Weibull <now@...>

Hi!

18 messages 2012/03/21
[#393953] Re: What’s the best way to check if a feature/class has been loaded? — Xavier Noria <fxn@...> 2012/03/21

Active Support has recently added qualified_const_* methods to Module

[#393954] Re: What’s the best way to check if a feature/class has been loaded? — Xavier Noria <fxn@...> 2012/03/21

Ah, that won't work in 1.8.

[#393959] Re: What’s the best way to check if a feature/class has been loaded? — Nikolai Weibull <now@...> 2012/03/21

On Wed, Mar 21, 2012 at 16:43, Xavier Noria <fxn@hashref.com> wrote:

[#393960] Re: What’s the best way to check if a feature/class has been loaded? — Xavier Noria <fxn@...> 2012/03/21

On Wed, Mar 21, 2012 at 8:17 PM, Nikolai Weibull <now@bitwi.se> wrote:

[#393961] Re: What’s the best way to check if a feature/class has been loaded? — Nikolai Weibull <now@...> 2012/03/21

On Wed, Mar 21, 2012 at 20:48, Xavier Noria <fxn@hashref.com> wrote:

[#393962] Re: What’s the best way to check if a feature/class has been loaded? — Xavier Noria <fxn@...> 2012/03/21

On Wed, Mar 21, 2012 at 9:51 PM, Nikolai Weibull <now@bitwi.se> wrote:

[#393967] Re: What’s the best way to check if a feature/class has been loaded? — Nikolai Weibull <now@...> 2012/03/22

On Wed, Mar 21, 2012 at 22:11, Xavier Noria <fxn@hashref.com> wrote:

[#393969] Re: What’s the best way to check if a feature/class has been loaded? — Xavier Noria <fxn@...> 2012/03/22

On Thu, Mar 22, 2012 at 6:15 AM, Nikolai Weibull <now@bitwi.se> wrote:

[#394154] uninitialized constant SOCKSSocket — Resident Moron <lists@...>

I am running ruby 1.9.3 on a linux box. I would like to use

10 messages 2012/03/29

[#394160] Why z = Complex(1,2) rather than z = Complex.new(1,2)? — Ori Ben-Dor <lists@...>

What's this syntax, z = Complex(1,2), as opposed to z =

14 messages 2012/03/29

[#394175] shoes no such file to load -- rubygems — Mr theperson <lists@...>

I have installed shoes to develop GUI applications but when I try and

13 messages 2012/03/29

[#394201] Can't open url with a subdomain with an underscore — Jeroen van Ingen <lists@...>

I try to open the following URL: http://auto_diversen.marktplaza.nl/

10 messages 2012/03/30

[#394222] Ruby openssl ECC help plz — no name <lists@...>

I am confused on how to properly export public ECC key. I can see it

13 messages 2012/03/31

Re: for enumerators: last, prev ?

From: Ralph Shnelvar <ralphs@...32.com>
Date: 2012-03-12 22:03:43 UTC
List: ruby-talk #393813
Bartosz,

The convention is to bottom post.  I am moving your comment to the right place and responding.

Monday, March 12, 2012, 11:51:54 AM, you wrote:


BD> 2012/3/12 Ralph Shnelvar <ralphs@dos32.com>:
>> I see that enumerators have the methods rewind and next.
>>
>> Are there equivalent methods "end" and "prev"?
>>
>> I see reverse_each ... but what if I do have a large enumerable object and don't want the intermediate array created?
>>
>>
>>
>> The documentation ( http://ruby-doc.org/core-1.9.3/Enumerable.html#method-i-reverse_each ) for reverse each says:
>>
>> - - -
>>
>> reverse_each(*args) {|item| block } ? enum click to toggle source
>> reverse_each(*args) ? an_enumerator
>>
>> Builds a temporary array and traverses that array in reverse order.
>>
>> If no block is given, an enumerator is returned instead.
>>
>> - - -
>>
BD> Enumerators can only "move" in one direction - forward. #end would be
BD> useless for many (for ex. (1..Float::INFINITY).each - this one never
BD> ends), providing #prev would be equivalent to remembering all of
BD> values yielded so far (unpractical, we don't have infinite memory).

BD> -- Matma Rex

For ranges, all you need define is the inverse of the succ function (which must be defined in order to "go forwards").

By the way,
(99_999_999_990..100_000_000_000).last(3) works just fine but
(1..100_000_000_000) seems to hang in a loop.  I suspect Ruby is constructing a temporary array.

Ruby seems not to be clever at all about ranges.





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