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Groups > comp.lang.forth > #41981

Re: Strings and numbers

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humptydumpty <ouatubi@gmail.com> writes:
> Is noteworthy that dynamically using variables, unlike using locals,
> permits factoring.

Yeah, I think the code I posted with the locals could have been arranged
to use the stack (maybe easier with 2 args instead of 3) but I didn't
feel up to the effort.  Static variables of course don't work with
recursive functions where the locals need different values at different
call levels.  I wrote some other recursive code a while back where I
didn't want to even think about how to get rid of the locals.  Here you
do it by carefully modifying the global, using it, then unmodifying it
in order to backtrack.  I think for the most part, the no-locals style
is harder for this sort of thing.  But it's nice to see you and Richard
posting code without them.

> Just for factoring sake, under dynamically use of variable 'Bmp':
> : >{	]] dup @ 2>R [[ ; IMMEDIATE
> : }	]] R> R>   ! [[ ; IMMEDIATE

What are ]] and [[ ?  They're not in the gforth manual word index.

> 	VARIABLE Bmp VARIABLE N
> 	DEFER run ( u -- )

What's the purpose of deferring run?  I thought maybe it was for
mutually recursive functions but I didn't see anything that needed it.

> 				prologue
> 				2dup N @ swap - mod 0=
> 				IF RECURSE THEN
> 				epilogue

I guess this uses less memory than leaving all that stuff on the stack
in the locals version.  

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Strings and numbers Steve Graham <solitary.wanderer52@gmail.com> - 2015-08-03 13:24 -0700
  Re: Strings and numbers Julian Fondren <julian.fondren@gmail.com> - 2015-08-03 13:51 -0700
    Re: Strings and numbers "Rod Pemberton" <boo@fasdfrewar.cdm> - 2015-08-03 17:38 -0400
    Re: Strings and numbers Steve Graham <solitary.wanderer52@gmail.com> - 2015-08-03 14:44 -0700
  Re: Strings and numbers Paul Rubin <no.email@nospam.invalid> - 2015-08-03 20:59 -0700
    Re: Strings and numbers Steve Graham <solitary.wanderer52@gmail.com> - 2015-08-04 12:19 -0700
      Re: Strings and numbers "WJ" <w_a_x_man@yahoo.com> - 2015-08-07 09:29 +0000
        Re: Strings and numbers "WJ" <w_a_x_man@yahoo.com> - 2015-09-04 15:14 +0000
          Re: Strings and numbers "WJ" <w_a_x_man@yahoo.com> - 2015-09-07 19:34 +0000
            Re: Strings and numbers Julian Fondren <julian.fondren@gmail.com> - 2015-09-08 11:48 -0700
            Re: Strings and numbers Paul Rubin <no.email@nospam.invalid> - 2015-09-09 00:41 -0700
              Re: Strings and numbers Richard Todd <richard.wesley.todd@gmail.com> - 2015-09-10 00:32 -0700
                Re: Strings and numbers Richard Todd <richard.wesley.todd@gmail.com> - 2015-09-10 10:29 -0700
                Re: Strings and numbers Paul Rubin <no.email@nospam.invalid> - 2015-09-10 17:22 -0700
                Re: Strings and numbers Richard Todd <richard.wesley.todd@gmail.com> - 2015-09-10 21:34 -0700
                Re: Strings and numbers humptydumpty <ouatubi@gmail.com> - 2015-09-11 02:16 -0700
                Re: Strings and numbers humptydumpty <ouatubi@gmail.com> - 2015-09-11 07:33 -0700
                Re: Strings and numbers Paul Rubin <no.email@nospam.invalid> - 2015-09-13 00:12 -0700
                Re: Strings and numbers humptydumpty <ouatubi@gmail.com> - 2015-09-13 02:09 -0700
                Re: Strings and numbers Paul Rubin <no.email@nospam.invalid> - 2015-09-11 15:53 -0700
                Re: Strings and numbers Andrew Haley <andrew29@littlepinkcloud.invalid> - 2015-12-18 16:02 -0600
            Re: Strings and numbers "WJ" <w_a_x_man@yahoo.com> - 2015-09-12 23:38 +0000
              Re: Strings and numbers "WJ" <w_a_x_man@yahoo.com> - 2015-09-13 19:41 +0000
            Re: Strings and numbers "WJ" <w_a_x_man@yahoo.com> - 2015-11-29 18:09 +0000

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