Path: utzoo!mnetor!uunet!husc6!cmcl2!rutgers!ames!sdcsvax!ucsdhub!hp-sdd!hplabs!hpda!hpcupt1!hpcllla!hpclisp!hpclscu!shankar
From: shankar@hpclscu.HP.COM (Shankar Unni)
Newsgroups: comp.lang.pascal
Subject: Re: Conformable Arrays
Message-ID: <950004@hpclscu.HP.COM>
Date: 21 Dec 87 23:32:39 GMT
References: <1472@cartan.Berkeley.EDU>
Organization: HP ITG/ISO Computer Language Lab
Lines: 51

>
>  2)  Probably most importantly, are conformable arrays standard ?  Cooper
>      says something about Level 1 and Level 2 Pascal.  What finally happened ?
>

Yes, there is an ISO standard for pascal that has things called "Conformant
Arrays". The syntax is as follows:

TYPE
   myarr = array [1..5] of mytype;    (* say *)

VAR
   myvar : myarr;

   PROCEDURE proc (VAR myparm : ARRAY [lowbnd..highbnd : INTEGER] of mytype);
   BEGIN
   ...
   (* you can access "lowbnd" and "highbnd" as read-only variables here, for
      example as loop indices *)
   ...
   END;

...
BEGIN
   proc (myvar);
   (* this passes myvar as the actual array, and 1 and 5 as lowbnd and highbnd,
      respectively *)
END;

>
>  1)  How do you pass part of an array, like in fortran ?  The fortran
>      code below passes the segment a(5),a(6),a(7) (or even more, I know).
>      What is the analogy in Pascal.  I tried to get it from Cooper's books,
>      but it wasn't clear.
>
>	  real a(10)
>	  call sub(a(5),3)
>
>	  subroutine sub(a,n)
>	  real a(n)
>	   .....

As far as I know, there is no good, clean way to do exactly this in Pascal.


-----------------------------------------------------------------------------
Shankar Unni
Unix Mail: shankar@hpclscu , shankar%hpclscu@hpda
HPMAIL:    SHANKAR UNNI/HPUNIX/UX
Telnet:    1-447-5797
-----------------------------------------------------------------------------