Re: colon colon

Date	2012-07-12 19:58 +0200
From	Fanzo <cristianof6@gmail.com>
Newsgroups	comp.lang.forth
Subject	Re: colon colon
References	<4ffc6c61$0$1375$4fafbaef@reader2.news.tin.it> <jtjbpa$udi$1@speranza.aioe.org> <4ffdcf39$0$1378$4fafbaef@reader2.news.tin.it> <jtm4g7$dr9$1@speranza.aioe.org>
Message-ID	<4fff0f8a$0$1390$4fafbaef@reader2.news.tin.it> (permalink)
Organization	TIN.IT (http://www.tin.it)

Show all headers | View raw

Rod Pemberton wrote:

> For DTC or ITC, the CFA field tells whether to execute or interpret the
> word.  So, the first word of xt's is interpreted and the second word with
> OPCODEs is executed.  It's called a primitive or low-level word.  The first
> word has it's CFA set to ENTER.  ENTER is an address interpreter.
> Basically, ENTER calls the xt's.  The second word has it's CFA set to the
> address of the routine.

I know ITC, my first version of my forth was ITC in C,
but then i changed (no interest in speed comparison).
I see the STC more simple for me. And also less structure at the 
beginning to change it later. My variables are routine themself.

> 
> DROP can be an unused POP.  Do you have a spare register?
> 

The assembler is a virtual machine of 24 opcodes (POP is one of them 
that just put TOS in the bin)

> DROP might be implementable in others ways, e.g.:
> 
>  0 AND OR
> 
>  >R RDROP
> 
>  A!  \ store into variable
> 

I used my custom word "now" to compile "POP RET" and execute it when 
needed. But this routine get compiled in a transient buffer of 30 CELLs.
There, every opcode needed can be put afterward to execute something on 
the fly.

Goodbye

Back to comp.lang.forth | Previous | Next — Previous in thread | Find similar

Thread

colon colon Fanzo <cristianof6@gmail.com> - 2012-07-10 19:58 +0200
  Re: colon colon "Rod Pemberton" <do_not_have@notemailnot.cmm> - 2012-07-11 04:01 -0400
    Re: colon colon Mark Wills <markrobertwills@yahoo.co.uk> - 2012-07-11 02:01 -0700
    Re: colon colon Fanzo <cristianof6@gmail.com> - 2012-07-11 21:11 +0200
      Re: colon colon "Rod Pemberton" <do_not_have@notemailnot.cmm> - 2012-07-12 05:15 -0400
        Re: colon colon Fanzo <cristianof6@gmail.com> - 2012-07-12 19:58 +0200

csiph-web