Re: Clause "with and use"

[18k11tm001@sneakemail.com (Russ)]

"Warren W. Gay VE3WWG" <ve3wwg@cogeco.ca> wrote in message news:<atRpb.673$143.30323@news20.bellglobal.com>...

> I personally think it is necessary to keep encouraging
> the programmers to think about more than their own
> convenience. This is what much of the += ballyhoo is
> all about.

From my perspective, that is simply your persistent misunderstanding
of the "+= ballyhoo". I have given several good reasons in favor of
"+=" (or ":+"). Note that "saving keystrokes" is not one of them,
despite the persistent bleatings to the contrary. And what is wrong
with "programmer convenience," when there is no downside? Do you think
"programmer inconvenience" is an inherent virtue?

Here are the reasons I have given in favor of "+=":

1. "+=" (":+") relieves the *reader* of the code of the task of
verifying that the twice-named variable is indeed the same variable
repeated twice. And it does so without the cumbersome mechanism of
renaming and explicity creating a new scope.

2. "+=" (":+") provides a *standard* symbol for common operations on
scalar types. Yes, that is a "programmer convenience" because it
relieves the programmer of the make-work task of defining (or
instantiating) his own "Inc" operator for many different types. It
also reduces the possibility that the programmer could err in doing
something that the compiler could do for him. I don't know about you,
but I find that good compilers are usually less error-prone than me.

3. "+=" (":+") provides a *standard* symbol for efficient
vector/matrix (and other) operations, thus preventing a proliferation
of user-named procedures such as

   Add ( A, To=> B ); -- or
   MatrixAdd ( source=>A, destination=>B ); -- or
   MatrixAddition ( from=>A, inplace=>B ); -- etc., etc.
   ...

By the way, if a C/C++ programmer writes x = x + 2; in lieu of x += 2,
chances are he is not a top-notch programmer. But Ada forces such bad
style, and that's bad style itself.