variable declaration

[Alexander]

Hi, Elspeth!

09 feb 2005 at 14:44, Elspeth Thorne wrote:
 >> You may say: give better names for your variables! Ha, I'am often
 >> don't understand that they mean! They are written for me by an
 >> engineer!
 ET> Hang on, though - if you don't understand what you are programming,
 ET> then how can you check if it's correct?
...skipped...
 ET> You'd hit the same issues (precisely the same issues) with any
 ET> language, if you flat-out do not know what you are doing - or trying
 ET> to do.

 ET> Admittedly, I have somewhat limited experience, so my word is not
 ET> gospel, or even necessarily well-informed.

I will inform you:) Let say you are working with the team of engineers. They
develop a project of new building, and they need some calculations of solidness
of metall constructions, specific for such kind of building. Such calculations
are rather complex, so they can't wrote program (or smth else) themselves. But
they can wrote and explain algorithm with calculations.
If you want understand their formulas, you must learn theoretical mechanicks,
resistance of materials, builder's standarts and rules (I'm not sure I
translate titles of the disciplines correctly). It will take a year, minimum.
But you have no such time - deadline is much closer:)

As for me, I _HATE_ such kind of job:) But sometimes it happens. And, after
some years, when you see the final result of such job, you fill some special
feelings. It differ from result of purely programmer's work. The result is big,
real, it may work for people during tens (or may be hundred) years.

Main problem in programming - programmer "look to the wrong place" or "overlook
coefficient", ... . Main weapon to fight with them - tests. We do it this way.
After engineer wrote an "algorithm", he take a calculator and began to work
according to it (it also help him to find "bugs"). Final result, and all
intermediate results are written. Every separate part of calculations (separate
function in program) tested separately and in whole.

But tests are not a silver bullet. static checking is also very usefull. What's
why I feel variable declaration (or explicit variable definition) may help.

Alexander, zatv at bk.ru