D const design rationale

[Daniel Keep]

Walter Bright wrote:
> ... A lot of people use Python, and are forced
> to mix in C++ to speed up the slow parts. It would be much simpler for
> them if they could use the same language for both.

I'll have to disagree on this.  I used Python for my third year
comp.sci. group project, and it made things a hell of a lot easier.
Most of the code was dealing with the GUI, with only a few math-heavy
parts written by myself.

Using Python for the mathy parts made them so much easier to debug it
wasn't funny, and I've never seen anything that could touch Python for
writing sane GUI code.

In the end, I had to convert some of the slower code from Python to C,
but that was basically a trivial exercise.  Pyrex allows you to write
"Python-like" code that compiles directly to C that makes writing the
native module wrapping C code a non-issue.

If I'd used just C++, the GUI coding would have driven me completely
insane.  If I'd been restricted to an interpreted language, our app
would have been slow as molasses.  By using Python, we got the best of
both worlds :)

In a wacky kind of way, one of the reasons I chose Python was *because*
it could be easily optimised.  True, it had to be done in a different
language, but there was almost no effort required to do so, so I never
had to fear hitting a performance ceiling.

	-- Daniel