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From: shankar@hpclscu.HP.COM (Shankar Unni)
Newsgroups: comp.sys.hp
Subject: Re: HP9000 Pascal Buglist / Wishlist
Message-ID: <1340075@hpclscu.HP.COM>
Date: 5 Oct 89 22:41:38 GMT
References: <2258@mva.cs.liv.ac.uk>
Organization: Hewlett-Packard Calif. Language Lab
Lines: 87

> 1. Extremely large executable size (On Series 800 machines only)
>    -------------------------------

Well, this is sort of a misfeature, especially considering that Pascal does
not guarantee initialization at load time..

This has been reported more than once, but I'm not sure if a fix is
forthcoming in the *near* future, since it's so easy to work around (after
all, how many of these arrays do you have? You could easily "new" this
arrays on the heap).

> 2. Otherwise clause in a Case statement is compulsory at run-time
>    --------------------------------------------------------------

All for the sake of the "Pascal" spirit. We try to catch as many exceptions
as possible, and according to the Pascal standard, this is an error, and
quality implementations must catch it. I therefore don't consider this a
bug, but consider the other compilers buggy in not catching this.

> 5. The + operator for strings is fussy about its operands
>    ------------------------------------------------------

I agree. It could be a little more flexible.

> The rest of these points are a wishlist for HP Pascal:
> 1. Array slicing
>    -------------
>    var fred : array [ 1..7 , 1..7 ] of integer ;
>    begin fred [ 1 , ] := fred [ 2 , ] end ; { OK, so it's uninitialised... }

Actually, the syntax for that is

        fred[1] := fred[2];

I.e., if fred is a 2-d array, fred[1] is a one-d array, and fred[1,1] is an
element. 

> 2. Constant assignment to arrays (and other types ?) in the var section
>    --------------------------------------------------------------------
>    var fred : array [ 1..2 , 1..2 ] of integer :=
>               ( ( 17 , 6 ) , ( 13 , -2 ) ) ;

There is an ugly way of doing this (at least in the 800 pascal):

Name each subtype of fred explicitly:

    type
	oneDarray = array[1..2] of integer;
	twoDarray = array[1..2] of oneDarray;
    var
	fred : twoDarray;
    const
	fred_init = twoDarray [ oneDarray [17, 6], oneDarray [13, -2] ];
    begin
	fred := fred_init;  /* initialize at one shot */
    end.

There is still no way to initialize at compile-time, but this is better
than nothing..

> 3. Access to external ints in C library routines
>    ---------------------------------------------

This is one of the sore points. Both Pascal's provide ways to do this, but
they both rely on tricks of the implementation, and they are incompatible
with each other, so I won't waste your time telling you about them.

> As I think has already been mentioned, it is clear that Series 300 and Series
> 800 Pascal are written by different people within HP. This does lead to

Gee, how did you guess? :-)

Seriously, though, there are strenuous efforts under way to converge them
to a common base. Your suggestions are valuable for this exercise. If you
have any sort of an HP support contract, please also report any problems
you find to your HP support rep, so that *you* can be sure that they are
officially logged and recognized. I'll forward these comments to the Pascal
team in any case.

P.S.: there is an ANSI committee currently working (in the late stages) on a
standard for "Extended Pascal", which will give you most of what you wished
for above. The committee is X3J9. See if you can get a copy of the draft
from somewhere. Let your HP rep know if you're interested.
-----
Shankar Unni ("ex-Pascal grunt")          E-Mail:
Hewlett-Packard California Language Lab.     Internet: shankar@hpda.hp.com
Phone : (408) 447-5797                       UUCP:     ...!hplabs!hpda!shankar