From: johnrreagan@earthlink.net   
      
   On 1/14/2025 11:03 AM, Arne Vajhøj wrote:   
   > On 1/13/2025 11:38 PM, Lawrence D'Oliveiro wrote:   
   >> On Mon, 13 Jan 2025 21:08:11 -0500, John Reagan wrote:   
   > ### They are probably most useful for modules, but why not allow   
   > ### them for programs?   
   >>> Extended Pascal says only MODULEs so we just didn't   
   >>> think about allowing them in PROGRAMs even though we allow [INITIALIZE].   
   >>   
   >> Not sure what the point would be in having them in PROGRAMs, anyway.   
   >   
   > Definitely most useful for modules. I was just wondering   
   > why not allow it in programs as well.   
   >   
   > It seems to have been explicit disallowed. The error message is:   
   >   
   > %PASCAL-E-TOPROGRAM, TO BEGIN/END DO not allowed in PROGRAM   
   >   
   > If one start to look for something useful then I would say that   
   > TO BEGIN is just code after PROGRAM BEGIN, but TO END is more   
   > than just code before PROGRAM END as it get triggered by other   
   > program exits as well.   
   >   
   > Demo:   
   >   
   > $ type m.pas   
   > module m(input,output);   
   >   
   > to begin do writeln('m to begin');   
   > to end do writeln('m to end');   
   >   
   > end.   
   > $ type p.pas   
   > [inherit('m', 'sys$library:starlet')]   
   > program p(input,output);   
   >   
   > [initialize]   
   > procedure init;   
   >   
   > begin   
   >     writeln('init');   
   > end;   
   >   
   > procedure done;   
   >   
   > begin   
   >     writeln('done');   
   > end;   
   >   
   > var   
   >     ent : integer64;   
   >     desblk : array [1..4] of integer;   
   >     cond : integer;   
   >   
   > begin   
   >     writeln('begin');   
   >     desblk[1] := 0;   
   >     desblk[2] := iaddress(done);   
   >     desblk[3] := 0;   
   >     desblk[4] := iaddress(cond);   
   >     $dclexh(desblk);   
   >     $get_entropy(ent, 8);   
   >     if (ent mod 2) = 0 then $exit(SS$_NORMAL);   
   >     $canexh(desblk);   
   >     writeln('end');   
   > end.   
   > $ pas/env m   
   > $ pas p   
   > $ link p + m   
   > $ run p   
   > m to begin   
   > init   
   > begin   
   > end   
   > m to end   
   > $ run p   
   > m to begin   
   > init   
   > begin   
   > done   
   > m to end   
   > $ run p   
   > m to begin   
   > init   
   > begin   
   > end   
   > m to end   
   > $ run p   
   > m to begin   
   > init   
   > begin   
   > done   
   > m to end   
   >   
   > Arne   
   >   
   I just looked.  The TO BEGIN/END DO was added back in 1987 by a former   
   developer (not me).  I suspect that since the Extended Pascal standard   
   only allows them in MODULEs, not PROGRAMs, that he just followed the   
   draft standard at that point without considering that TO END DO is a   
   little better than "code at the end".   
      
   --- SoupGate-DOS v1.05   
    * Origin: you cannot sedate... all the things you hate (1:229/2)