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From: ephram@violet.berkeley.edu
Newsgroups: comp.sys.ibm.pc
Subject: Turbo Pascal bug? or feature?
Message-ID: <24349@agate.BERKELEY.EDU>
Date: 12 May 89 13:33:56 GMT
Sender: usenet@agate.BERKELEY.EDU
Reply-To: ephram@violet.berkeley.edu ()
Organization: University of California, Berkeley
Lines: 75

Here is what I consider a minor bug with turbo pascal (V.5.0 maybe 4 others
untested).  It has to do with comments.  The basic problem is with nesting
comments of the same "type", ie { or (*.  The code that follows illustrates
some of my gripe.

This is legal in TP5

begin
  {{ }
end.

This is illegal in TP5

begin
  {{ }}
end.

This is legal in TP5

begin
  { (* }
end.

This is illegal in TP5

begin
  { (* } *) }
end.

And, Finally this is illegal in TP5

begin
  { }}
end.

My point is that there is a lot of inconsistancy in levels of parenthesization
(sp?).  It crops up in code every once in a while and can be hard as h*ll to 
find. if you forget to close your comment then whole sections of code can be
commented out (usually easy to find :-).  Worse yet if you have succesive lines
with comments one line can be commented out and not be easy to notice at all.

begin
  writeln ('this program inc''s I and prints it out');  { emit stupid message}
  while false do begin               {loop forever               
    inc (i);                         {do the increment}
    writeln (i);                     {and print it out}
  end;
end. 

This will print whatever "i" was forever.  If that "inc i" step was a 
Procedure that called other Procedures etc. You would wonder "what is wrong
with my procedure's?" and be off on a wild goose chase.

My basic point is that I think that TP should check parenthetical levels at
least for the illegal case of {{ }.  I suppose that the structure of the
parenthesis would then cause the { char to never be use inside of a comment
but the } char can never be used as such anyway.

What do other people think?  is this a bg or a feature to be able to block out
multiple sections of code with only changing some of the {'s?

{ procedure_1;

{ prodecure_2;

{Procedure_3;

}

is afterall a legal construct.  
We must prevent those commies from compromising the integrity of our 
precious bodily fluids.      -Gen. Jack D. Ripper
Ephram Cohen                              ephram@violet.berkeley.edu
466 44th St.  #1                          3210 Tolman Hall
Oakland, CA 94609                         Berkeley, CA  94720