Path: utzoo!utgpu!water!watmath!clyde!att-cb!att-ih!pacbell!ames!ucsd!sdcc6!sdcc8!cs178abu
From: cs178abu@sdcc8.ucsd.EDU (John Schultz)
Newsgroups: comp.lang.modula2
Subject: Re: Anyone seen a good Amiga Pascal lately ?  Why not Modula-2?
Message-ID: <833@sdcc8.ucsd.EDU>
Date: 2 Apr 88 21:54:52 GMT
References: <764@ndsuvax.UUCP>
Reply-To: cs178abu@sdcc8.ucsd.edu.UUCP (John Schultz)
Organization: University of California, San Diego
Lines: 83



In article <764@ndsuvax.UUCP> ncreed@ndsuvax.UUCP (Walter Reed) writes:
>There are two major beefs I have with modula-2.
>1.  Modula does not allow a variable number of parameters in function calls.
>2.  Bitwise operators are not available (at least not standard.)
>Minor beef:
>    Begin end's required even when only one statment used.

  Addressing 1:  Register oriented AOT stack oriented as in C
(although I heard that Lattice now has register optimization).  This
is much faster runtime, although more verbose for the user.
Benchmark has C routines such as printf, etc., but you must first
initialize the parameter array before calling printf (still pretty
nice though).
  2.  Modula-2 has *ALWAYS* had bitwise operators.  They are:

     +  : inclusive OR
     *  : AND
     /  : exclusive OR

  These operators have special meaning only when applied to BITSET
types.  For example:

     CONST
       mask = BITSET(15);

     VAR
       rotation : CARDINAL;

     BEGIN
       rotation := 0;
          ...
       rotation := CARDINAL(BITSET(rotation+1)*mask);
          ...

  Here we can increment a value from 0 to 15 and back again without
any bounds checking.  In C we could do:

       rotation = (rotation + 1) & 0xf; or maybe
       rotation = ++rotation & 0xf; or maybe
       ++rotation &= 0xf;

  Much less typing, but the same result.

  The *only* time BEGINs are used in Modula-2 are for the start of
program code for PROCEDUREs or main MODULES.  Everything terminates
with an END.  This is an improvement over Pascal and C, as it stops
possible errors before they can start.

>Here is an example of why these things bother me.
>
>Pascal:
>	If (x = True) Then
>		WriteLn('Error #',e,' in line #',l,' detected.');
  Why not:
    IF x THEN printf(); END;

>M2 is too verbose.

  Yeah, well, everything you want is available in C.  Now, if you
want the MODULE construct, etc. native to M2, the 10000-30000 lines
per minute compilation times, "instant" linking, then take another
look at M2.

> Shifting...

  FROM SYSTEM IMPORT SHIFT  (* example code *)

   SHIFT(x,1)  x is unsgned, logical SL 
   SHIFT(x,1)  x is sgned, artihmetic SL
   SHIFT(x,-1) ... SR 

  It's all there.  Remember M2 was created for the development of
large, system level software (like operating systems).

  Other than for personal taste, and/or development
speed/portability, you can do anything on the Amiga with any of the
popular compiled languages available today.



  John