[Retros] Retractor 2.0 now available online
norbert.geissler at ng37.de
Sat Apr 10 17:11:44 EDT 2021
I tested the URL below a minute ago.
It does work ...
On 10.04.21 22:23, Theodore Hwa wrote:
> Make sure you use http:// and not https:// (and make sure you don't have
> a browser setting that automatically changes http to https).
> On Sat, 10 Apr 2021, Alexander George wrote:
>> Hi. I keep getting the message:
>> The requested URL /~hwatheod/retractor2/retractor.html was not found
>> on this server.
>> On Sat, Apr 10, 2021 at 1:56 AM Theodore Hwa
>> <hwatheod at cs.stanford.edu> wrote:
>> Hello retro enthusiasts,
>> Retractor 2.0 is now available online as an application in your
>> browser at
>> For those not familiar, Retractor is a program for exploring retro
>> problems. It lets you setup a position and play backwards from
>> it, and
>> warns you if it detects an illegal position. It reports the
>> number of
>> captures and promotions in a position. It can also solve some
>> "Last N
>> moves" problems.
>> For those of you who have been around this list for a while,
>> Retractor 2.0
>> is the successor of Retractor 1.0 which was a Windows application
>> developed by myself and Chad Whipkey in 1998.
>> Right now, Retractor 2.0 is pretty much a straight port of
>> Retractor 1.0
>> immediate items for improvement are (1) taking promotions into
>> when counting pawn captures, and (2) a more general method for
>> of illegal retro-cages (right now, some common cases are
>> I am using the "Last Single Move" problems (types A-D) at
>> https://www.janko.at/Retros/Records/LastMove/index.htm as
>> benchmarks for
>> improving Retractor. When going through those problems, I found
>> that when
>> Retractor cannot solve one of them, it's usually because of (1)
>> If you are interested in the source code, it is available on
>> github at:
>> Any and all feedback, comments, contributions for Retractor are
>> appreciated! You can contact me at this email address, or on the
>> page above.
>> Ted Hwa
>> Retros mailing list
>> Retros at janko.at
>> Alexander George
>> Department of Philosophy
>> Amherst College
>> Amherst, MA 01002
> Retros mailing list
> Retros at janko.at
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I feel the ardour of a lover, the humility of a disciple.
(Herbert Russell Wakefield)
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