Re: basic BASIC question

On 1/31/2025 2:24 PM, Dan Cross wrote:

In article <679d001e$0$713$14726298@news.sunsite.dk>,
Arne Vajhøj  <arne@vajhoej.dk> wrote:

On 1/31/2025 11:39 AM, Dave Froble wrote:

On 1/31/2025 10:18 AM, Arne Vajhøj wrote:

Is it common to use:
>
declare integer constant TRUE = -1
declare integer constant FALSE = 0
>
>
?

>
It works.  Doesn't really matter if declared a constant.  Zero is false,
anything else is true.  Using 1 vs -1 has been more my experience.

>
I got the impression that the manual/compiler prefer -1 over 1.
>
print not 0%
>
does print -1.

 This sort of makes some sense when one considers the bit
representation of `-1` on a 2s complement machine (all bits 1).

True.
But there is no consistency between languages.
$ type dump.for
       subroutine dump(v)
       integer*4 v
       write(*,*) v
       end
$ for dump
$ type logfun.for
       program logfun
       call dump(.true.)
       call dump(.false.)
       end
$ for logfun
$ link logfun + dump
$ run logfun
          -1
           0
$ type logfun.pas
program logfun(input,output);
[external]
procedure dump(%ref v : boolean); external;
begin
    dump(true);
    dump(false);
end.
$ pas logfun
$ link logfun + dump
$ run logfun
           1
           0
Arne