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Re: Genral advise and comments on callback style words

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On 2012-11-08 18:04:30 +0000, Josh Grams said:

> Chris Hinsley wrote: <201211081406178276-chrishinsley@gmailcom>
>> On 2012-11-08 13:54:42 +0000, Josh Grams said:
>>> Chris Hinsley wrote: <2012110713421835115-chrishinsley@gmailcom>
>>>> Folks I have implamented an Amiga style double linked list words set a
>>>> few days back and I have an emueration word as follows:
>>>> 
>>>> \ ( u xt lh -- ln | 0)
>>>> \ xt api is ( u ln lh -- ln | 0 )
>>>> : LISTHEAD-ENUMERATE-FORWARDS
>>>> 	0 >R
>>>> 	DUP LISTHEAD-GET-HEAD DUP
>>>> 	BEGIN
>>>> 		NIP DUP LISTNODE-GET-SUCC
>>>> 		DUP
>>>> 	WHILE
>>>> 		4 PICK 2 PICK 4 PICK
>>>> 		6 PICK EXECUTE DUP R!
>>>> 	UNTIL THEN
>>>> 	2DROP 2DROP DROP
>>>> 	R>
>>>> ;
>>> 
>>> And just out of curiosity, why are you calling GET-HEAD and then
>>> GET-SUCC before you do anything?  Doesn't that skip the first list node?
>> 
>> I'm keeping a 'look ahead' pointer to the next node in the list, as the
>> callback is allowed to trash the current node ! For instance it could
>> remove the node and then your left dangling !
> 
> Ah, I see.  I thought you were keeping the previous one and getting the
> successor of that after the XT returned.  Guess I didn't untangle the
> PICKs carefully enough.
> 
> Hrm...I still think it's wrong...unless LISTNODE-GET-SUCC does something
> really strange like ( node node -- node.next node ), then your WHILE is
> checking the successor to see if it's null, so you won't process the
> final element in the list...?  Or am I missing something again?
> 
> --Josh

In this forward enum case both HEAD and SUCC end up being just a ! 
because HEAD and SUCC are 0. But in the backwards enumeration TAIL and 
PRED are 8 and 4 respectivly.

Chris

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Genral advise and comments on callback style words Chris Hinsley <chris.hinsley@gmail.com> - 2012-11-07 13:42 +0000
  Re: Genral advise and comments on callback style words Chris Hinsley <chris.hinsley@gmail.com> - 2012-11-07 13:51 +0000
    Re: Genral advise and comments on callback style words Chris Hinsley <chris.hinsley@gmail.com> - 2012-11-07 13:56 +0000
  Re: Genral advise and comments on callback style words anton@mips.complang.tuwien.ac.at (Anton Ertl) - 2012-11-07 13:55 +0000
    Re: Genral advise and comments on callback style words Chris Hinsley <chris.hinsley@gmail.com> - 2012-11-07 15:29 +0000
      Re: Genral advise and comments on callback style words Chris Hinsley <chris.hinsley@gmail.com> - 2012-11-07 15:35 +0000
    Re: Genral advise and comments on callback style words Chris Hinsley <chris.hinsley@gmail.com> - 2012-11-07 15:32 +0000
    Re: Genral advise and comments on callback style words Chris Hinsley <chris.hinsley@gmail.com> - 2012-11-07 15:37 +0000
      Re: Genral advise and comments on callback style words anton@mips.complang.tuwien.ac.at (Anton Ertl) - 2012-11-08 16:31 +0000
        Re: Genral advise and comments on callback style words Chris Hinsley <chris.hinsley@gmail.com> - 2012-11-08 17:02 +0000
          Re: Genral advise and comments on callback style words anton@mips.complang.tuwien.ac.at (Anton Ertl) - 2012-11-08 17:07 +0000
          Re: Genral advise and comments on callback style words Mark Wills <forthfreak@gmail.com> - 2012-11-09 01:16 -0800
    Re: Genral advise and comments on callback style words Chris Hinsley <chris.hinsley@gmail.com> - 2012-11-07 15:41 +0000
      Re: Genral advise and comments on callback style words anton@mips.complang.tuwien.ac.at (Anton Ertl) - 2012-11-08 16:39 +0000
  Re: Genral advise and comments on callback style words Brad Eckert <hwfwguy@gmail.com> - 2012-11-07 08:07 -0800
    Re: Genral advise and comments on callback style words Chris Hinsley <chris.hinsley@gmail.com> - 2012-11-08 12:52 +0000
  Re: Genral advise and comments on callback style words humptydumpty <ouatubi@gmail.com> - 2012-11-07 13:04 -0800
    Re: Genral advise and comments on callback style words Chris Hinsley <chris.hinsley@gmail.com> - 2012-11-08 13:04 +0000
      Re: Genral advise and comments on callback style words Mark Wills <forthfreak@gmail.com> - 2012-11-08 06:34 -0800
        Re: Genral advise and comments on callback style words Chris Hinsley <chris.hinsley@gmail.com> - 2012-11-08 14:40 +0000
    Re: Genral advise and comments on callback style words Chris Hinsley <chris.hinsley@gmail.com> - 2012-11-08 13:14 +0000
      Re: Genral advise and comments on callback style words Chris Hinsley <chris.hinsley@gmail.com> - 2012-11-08 13:23 +0000
      Re: Genral advise and comments on callback style words Ouatu Bogdan <ouatubi@gmail.com> - 2012-11-08 13:45 +0000
        Re: Genral advise and comments on callback style words Chris Hinsley <chris.hinsley@gmail.com> - 2012-11-08 13:59 +0000
        Re: Genral advise and comments on callback style words Chris Hinsley <chris.hinsley@gmail.com> - 2012-11-08 14:02 +0000
          Re: Genral advise and comments on callback style words Chris Hinsley <chris.hinsley@gmail.com> - 2012-11-08 15:35 +0000
            Re: Genral advise and comments on callback style words Chris Hinsley <chris.hinsley@gmail.com> - 2012-11-08 16:24 +0000
              Re: Genral advise and comments on callback style words Chris Hinsley <chris.hinsley@gmail.com> - 2012-11-08 16:39 +0000
                Re: Genral advise and comments on callback style words Chris Hinsley <chris.hinsley@gmail.com> - 2012-11-08 16:57 +0000
                Re: Genral advise and comments on callback style words "Elizabeth D. Rather" <erather@forth.com> - 2012-11-08 07:56 -1000
  Re: Genral advise and comments on callback style words Josh Grams <josh@qualdan.com> - 2012-11-08 13:54 +0000
    Re: Genral advise and comments on callback style words Chris Hinsley <chris.hinsley@gmail.com> - 2012-11-08 14:06 +0000
      Re: Genral advise and comments on callback style words Josh Grams <josh@qualdan.com> - 2012-11-08 18:04 +0000
        Re: Genral advise and comments on callback style words Chris Hinsley <chris.hinsley@gmail.com> - 2012-11-08 19:36 +0000
        Re: Genral advise and comments on callback style words Chris Hinsley <chris.hinsley@gmail.com> - 2012-11-08 19:38 +0000
          Re: Genral advise and comments on callback style words Chris Hinsley <chris.hinsley@gmail.com> - 2012-11-08 19:42 +0000
    Re: Genral advise and comments on callback style words Chris Hinsley <chris.hinsley@gmail.com> - 2012-11-08 14:11 +0000
      Re: Genral advise and comments on callback style words Chris Hinsley <chris.hinsley@gmail.com> - 2012-11-08 14:31 +0000
        Re: Genral advise and comments on callback style words Chris Hinsley <chris.hinsley@gmail.com> - 2012-11-08 14:51 +0000
          Re: Genral advise and comments on callback style words Josh Grams <josh@qualdan.com> - 2012-11-08 18:23 +0000
            Re: Genral advise and comments on callback style words Chris Hinsley <chris.hinsley@gmail.com> - 2012-11-08 19:57 +0000
            Re: Genral advise and comments on callback style words Chris Hinsley <chris.hinsley@gmail.com> - 2012-11-08 20:04 +0000
              Re: Genral advise and comments on callback style words Chris Hinsley <chris.hinsley@gmail.com> - 2012-11-08 20:17 +0000
                Re: Genral advise and comments on callback style words Chris Hinsley <chris.hinsley@gmail.com> - 2012-11-08 20:29 +0000
                Re: Genral advise and comments on callback style words Chris Hinsley <chris.hinsley@gmail.com> - 2012-11-08 20:50 +0000

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