Re: How to Design an Application Programmers' Interface (API)

["E. Robert Tisdale" <edwin@netwood.net>]

Brendan Sechter <sgeos@granicus.if.org> wrote:

> Why hide anything?

So that the application programmer doesn't access
private data members directly by accident.

> Do not you have the option not to use it?

You use it only through library function calls
so that your application program will work
even if the definition of the data type changes
when you install a newer version of the library.


Gregory Pietsch wrote:

> If they wanted it, they'd be C++ programmers.  C is not C++.
> Why not cut through all the layers of OO obfuscation
> right down to the bare metal?
> That's what C gives you and C++ does not.
>
> Ah, yes --
> the distinction between the interface and the implementation.
> This is fundamental to OO.

No.  It doesn't necessarily have anything to do with objects.
It's just good programming practice and always has been.

> If I did that, I'd have to retest it to make sure that it worked.
> You can't be too careful.

Good for you!  But we're assuming here that
the library has already been thoroughly tested
so retesting shouldn't be necessary.

> The one thing that made me sick about C++
> when I first encountered it was that philosophical aspect.
> If you weren't doing things the way that the high priests wanted you to,
> you'd be banished to writing payroll programs in RPG,
> or worse, being called an unwashed heathen
> who was unworthy even to enter the computer room.
> OO has been hyped so much that you'd figure that
> it would solve world hunger and usher in an era of world peace.  NOT!
> OO is a tool; that's all it is.  I AM a competent C programmer;
> one visit to Richard Heathfield's K&R2 site would prove it
> (I've written about a dozen answers to the K&R2 problems).

This is all gobbledegook to you isn't it?  No,
OOP isn't going to solve world hunger and usher in an era of world peace.
It just makes it a lot easier to write safe and reliable computer programs
that other programmers can read, understand and maintain.
Good programmers can wade through all of the hype about OOP
and learn to use it effectively.  Hackers can't.
You may be able to program in C to your own satisfaction
but until you can understand the code that other C programmers are writing
and learn to write code the way that they do, you will remain a hacker
and no one will trust you with important programming assignments.