Re: 8 queens problem in Oforth

From	Paul Rubin <no.email@nospam.invalid>
Newsgroups	comp.lang.forth
Subject	Re: 8 queens problem in Oforth
Date	2015-03-22 13:55 -0700
Organization	A noiseless patient Spider
Message-ID	<87lhioah1n.fsf@jester.gateway.sonic.net> (permalink)
References	(6 earlier) <bf5f7457-17dc-46be-8262-c64d40181af3@googlegroups.com> <87619uav5r.fsf@jester.gateway.sonic.net> <9e9efbe7-b0c8-45a3-9d0a-3dea3651759e@googlegroups.com> <871tkhbvex.fsf@jester.gateway.sonic.net> <memt6i$7lf$1@dont-email.me>

Show all headers | View raw

Bernd Paysan <bernd.paysan@gmx.de> writes:
> Of course Forth has first-class functions.  We call them "xt", execution 
> tokens.  You can pass them as parameters to other words, you can return an 
> xt as result of a word, you can use xts to define higher order functions.

Hmm, ok, I hadn't thought of xt's as first-class functions but maybe
they are.  Is it possible to create them at runtime?  I.e. is there an
ANS portable way to do something like:

    \ given functions f and g, make a new function that composes them
    : compose ( xt1 xt2 -- xt3 ) .... ;

So this should work:

   ['] sin ['] sqrt compose constant sin-sqrt      => ok

   2e sin-sqrt execute f.       => 0.9877659459927356 ok

That number is sin(sqrt(2)).  "Compose" has made a new xt that combines
the actions of the previous two.  It's like adding two numbers in order
to create a new number.  I'd say that to call xt's first class
functions, you have to be able to do this.

Thread

8 queens problem in Oforth "WJ" <w_a_x_man@yahoo.com> - 2015-03-19 07:53 +0000
  Re: 8 queens problem in Oforth Paul Rubin <no.email@nospam.invalid> - 2015-03-19 08:58 -0700
    Re: 8 queens problem in Oforth Doug Hoffman <glidedog@gmail.com> - 2015-03-20 08:16 -0400
      Re: 8 queens problem in Oforth anton@mips.complang.tuwien.ac.at (Anton Ertl) - 2015-03-21 10:11 +0000
        Re: 8 queens problem in Oforth franck.bensusan@gmail.com - 2015-03-21 03:45 -0700
          Re: 8 queens problem in Oforth Paul Rubin <no.email@nospam.invalid> - 2015-03-21 14:14 -0700
            Re: 8 queens problem in Oforth franck.bensusan@gmail.com - 2015-03-21 14:28 -0700
              Re: 8 queens problem in Oforth Paul Rubin <no.email@nospam.invalid> - 2015-03-21 14:38 -0700
                Re: 8 queens problem in Oforth franck.bensusan@gmail.com - 2015-03-21 15:15 -0700
                Re: 8 queens problem in Oforth hughaguilar96@gmail.com - 2015-03-21 18:23 -0700
                Re: 8 queens problem in Oforth franck.bensusan@gmail.com - 2015-03-22 03:03 -0700
                Re: 8 queens problem in Oforth hughaguilar96@gmail.com - 2015-03-22 14:04 -0700
                Re: 8 queens problem in Oforth franck.bensusan@gmail.com - 2015-03-22 16:34 -0700
                Re: 8 queens problem in Oforth hughaguilar96@gmail.com - 2015-03-22 21:49 -0700
                Re: 8 queens problem in Oforth Raimond Dragomir <raimond.dragomir@gmail.com> - 2015-03-23 00:05 -0700
                Re: 8 queens problem in Oforth hughaguilar96@gmail.com - 2015-03-23 21:43 -0700
                Re: 8 queens problem in Oforth franck.bensusan@gmail.com - 2015-03-24 04:13 -0700
                Re: 8 queens problem in Oforth franck.bensusan@gmail.com - 2015-03-23 00:17 -0700
                Re: 8 queens problem in Oforth Paul Rubin <no.email@nospam.invalid> - 2015-03-21 19:47 -0700
                Re: 8 queens problem in Oforth franck.bensusan@gmail.com - 2015-03-22 08:41 -0700
                Re: 8 queens problem in Oforth Paul Rubin <no.email@nospam.invalid> - 2015-03-22 13:37 -0700
                Re: 8 queens problem in Oforth Bernd Paysan <bernd.paysan@gmx.de> - 2015-03-22 18:13 +0100
                Re: 8 queens problem in Oforth Paul Rubin <no.email@nospam.invalid> - 2015-03-22 13:55 -0700
                Re: 8 queens problem in Oforth "Alex McDonald" <blog@rivadpm.com> - 2015-03-22 21:08 +0000
                Re: 8 queens problem in Oforth Paul Rubin <no.email@nospam.invalid> - 2015-03-22 14:39 -0700
                Re: 8 queens problem in Oforth Paul Rubin <no.email@nospam.invalid> - 2015-03-22 14:50 -0700
                Re: 8 queens problem in Oforth Bernd Paysan <bernd.paysan@gmx.de> - 2015-03-22 22:58 +0100
                Re: 8 queens problem in Oforth Paul Rubin <no.email@nospam.invalid> - 2015-03-22 15:13 -0700
                Re: 8 queens problem in Oforth Bernd Paysan <bernd.paysan@gmx.de> - 2015-03-23 01:03 +0100
                Re: 8 queens problem in Oforth Paul Rubin <no.email@nospam.invalid> - 2015-03-22 17:33 -0700
                Re: 8 queens problem in Oforth Bernd Paysan <bernd.paysan@gmx.de> - 2015-03-23 02:37 +0100
                Re: 8 queens problem in Oforth hughaguilar96@gmail.com - 2015-03-22 20:53 -0700
                Re: 8 queens problem in Oforth Paul Rubin <no.email@nospam.invalid> - 2015-03-22 21:11 -0700
                Re: 8 queens problem in Oforth anton@mips.complang.tuwien.ac.at (Anton Ertl) - 2015-03-23 11:34 +0000
                Re: 8 queens problem in Oforth albert@spenarnc.xs4all.nl (Albert van der Horst) - 2015-03-23 19:31 +0000
                Re: 8 queens problem in Oforth Paul Rubin <no.email@nospam.invalid> - 2015-03-23 15:56 -0700
                Re: 8 queens problem in Oforth Bernd Paysan <bernd.paysan@gmx.de> - 2015-03-24 00:38 +0100
                Re: 8 queens problem in Oforth Paul Rubin <no.email@nospam.invalid> - 2015-03-23 19:08 -0700
                Re: 8 queens problem in Oforth hughaguilar96@gmail.com - 2015-03-30 05:02 -0700
                Re: 8 queens problem in Oforth hughaguilar96@gmail.com - 2015-03-30 05:08 -0700
                Re: 8 queens problem in Oforth "Alex McDonald" <blog@rivadpm.com> - 2015-03-30 15:36 +0100
                Re: 8 queens problem in Oforth Bernd Paysan <bernd.paysan@gmx.de> - 2015-03-23 16:46 +0100
                Re: 8 queens problem in Oforth Paul Rubin <no.email@nospam.invalid> - 2015-03-23 15:32 -0700
                Re: 8 queens problem in Oforth Bernd Paysan <bernd.paysan@gmx.de> - 2015-03-23 23:48 +0100
                Re: 8 queens problem in Oforth Paul Rubin <no.email@nospam.invalid> - 2015-03-23 16:14 -0700
                Re: 8 queens problem in Oforth hughaguilar96@gmail.com - 2015-03-22 17:54 -0700
                Re: 8 queens problem in Oforth "Alex McDonald" <blog@rivadpm.com> - 2015-03-22 23:09 +0000
                Re: 8 queens problem in Oforth Bernd Paysan <bernd.paysan@gmx.de> - 2015-03-22 22:11 +0100
                Re: 8 queens problem in Oforth Paul Rubin <no.email@nospam.invalid> - 2015-03-22 14:48 -0700
                Re: 8 queens problem in Oforth hughaguilar96@gmail.com - 2015-03-22 15:11 -0700
                Re: 8 queens problem in Oforth anton@mips.complang.tuwien.ac.at (Anton Ertl) - 2015-03-23 11:29 +0000
                Re: 8 queens problem in Oforth albert@spenarnc.xs4all.nl (Albert van der Horst) - 2015-03-23 12:20 +0000
                Re: 8 queens problem in Oforth hughaguilar96@gmail.com - 2015-03-22 14:21 -0700
                Re: 8 queens problem in Oforth Coos Haak <chforth@hccnet.nl> - 2015-03-22 22:30 +0100
            Re: 8 queens problem in Oforth anton@mips.complang.tuwien.ac.at (Anton Ertl) - 2015-03-23 14:45 +0000
              Re: 8 queens problem in Oforth Paul Rubin <no.email@nospam.invalid> - 2015-03-23 14:53 -0700
                Re: 8 queens problem in Oforth "Elizabeth D. Rather" <erather@forth.com> - 2015-03-24 09:16 -1000
                Re: 8 queens problem in Oforth Paul Rubin <no.email@nospam.invalid> - 2015-03-24 12:40 -0700
                Re: 8 queens problem in Oforth anton@mips.complang.tuwien.ac.at (Anton Ertl) - 2015-03-30 12:24 +0000
          Re: 8 queens problem in Oforth Coos Haak <chforth@hccnet.nl> - 2015-03-21 22:27 +0100
  Re: 8 queens problem in Oforth "WJ" <w_a_x_man@yahoo.com> - 2015-03-19 20:31 +0000
  Re: 8 queens problem in Oforth "WJ" <w_a_x_man@yahoo.com> - 2015-03-19 20:35 +0000
  Re: 8 queens problem in Oforth "WJ" <w_a_x_man@yahoo.com> - 2015-03-21 17:31 +0000
    Re: 8 queens problem in Oforth "WJ" <w_a_x_man@yahoo.com> - 2015-03-21 20:50 +0000
    Re: 8 queens problem in Oforth "WJ" <w_a_x_man@yahoo.com> - 2015-03-21 21:52 +0000

csiph-web