Re: ada writing guide

["Jeffrey D. Cherry" <jdcherry@utech.net>]

Robert Dewar wrote:
> 
> I find the extra ); on its own line offensive and unnatural,
> just as clear, and much easier on the eye to write
> 
> >    procedure Foo
> >       (D : in out Data;
> >        C : in     Data);
> 
> In GNAT we prefer to put things on a single line:
> 
> >    procedure Foo (D : in out Data; C : Data);
> 
> If they fit comfortably on one line, and use the form with
> one line per parameter only if that is not the case.

I quite agree that if a complete declaration can appear on one
line, it should not be arbitrarily broken up into two or more
lines.  I also agree with the ");" looking silly when it's 
on a line by itself.  The part about "in" mode for parameters
(not quoted above, but in the original post) I would also 
agree with, especially with function parameters.  Now 
here is where I stray ... just a bit.

I like the following form for a subprogram declaration:

    procedure Foo(
       D : in out Data;
       C : in     Data);

There are two subtle differences.  First, I like to put the
opening parenthesis on the line with the subprogram name.
This allows the parameter names to line up starting in the
same column.  Second, I don't leave a space between the 
subprogram name and the opening parenthesis.  I'm pretty
comfortable with the first point while the second I find is
debatable.

Personally, I eliminate the space between a subprogram name 
and its opening parenthesis because it handles parentheses 
consistently when they are associated with an identifier.  
However, this might _not_ be the more readable practice.  
Consider the following contrived example:

procedure Silly is
   function foobar(a : float) return integer is
   begin -- foobar
      return integer(float'truncation(a));
   end foobar;
   f : float := 3.33;
   i : integer;
   n : array(1..5) of integer := (5, 6, 7, 8, 9);
begin -- Silly    
   i := foobar(f) + n(2);
end Silly;

Notice the consistency in the assignment statement.  But is
it more readable to write:

   i := foobar (f) + n(2);

This may give the reader a subtle indication that foobar is
a function call while n is an array.  I am curious to hear 
what others think of this practice ... is it just silly to 
worry about or does it indeed improve the readability of 
an expression?  

-- 
Regards,
Jeffrey D. Cherry
Senior IV&V Analyst
Logicon Space and Information Operations
Logicon Inc.
a Northrop Grumman company