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Re: [gforth] words backwards
From: |
David Boyd CW |
Subject: |
Re: [gforth] words backwards |
Date: |
Fri, 19 May 2017 16:47:52 +0000 |
-----Original Message-----
From: Bernd Paysan [mailto:address@hidden
Sent: Friday, May 19, 2017 12:24 PM
To: address@hidden
Cc: Dennis Ruffer <address@hidden>; David Boyd CW <address@hidden>
Subject: [EXTERNAL] Re: [gforth] words backwards
Am Freitag, 19. Mai 2017, 18:09:30 CEST schrieb Dennis Ruffer:
> Since Forth dictionaries are typically, singly linked lists, it would
> take memory and time to reverse the order.
Yes, but on a desktop system, we actually have that memory. And time is even
less important. This does it, by converting the list into an array and then
stepping backwards through that array:
Variable words[]
: words ( -- )
[: words[] dup $[]# swap $[] ! true ;] context @ traverse-wordlist
source nip 1+ words[] $@ bounds cell- swap cell- U-DO
I @ .word
cell -LOOP drop
words[] $free ;
Works in the current development system.
--
Bernd Paysan
"If you want it done right, you have to do it yourself"
net2o ID: kQusJzA;address@hidden(dQ*
http://bernd-paysan.de/
Thanks so much, exactly what I was looking for.