RE: Using Ada for device drivers? (Was: the Ada mandate, and why it collapsed and died)

[Lionel.DRAGHI@fr.thalesgroup.com]

| -----Message d'origine-----
| De: mcq95@earthlink.net [mailto:mcq95@earthlink.net]
...
| This is one of the biggest misconceptions about type-safety and the
| languages that utilize it: that its primary purpose is just to help
| avoid bugs.  (And this is a misconception held by many Ada programmers
| as well.)
....
| The proper definition of types for an application allows the embedding
| of vast quantities of information that is there just for the asking by
| the application.
Not just application, but also code reader.

...
|   type Altitude is digits 6.0 range -100.0 .. 50_000.0;
For me, the main point here in this declaration is to move more programmer's
knowledge into the code than possible in any other comparable language.
This knowledge will otherwise resides in the comments, or some doc, or just
nowhere.

In consequence:
- the language is able to provide usefull attributes,
- code readability improve,
- one will reduce documentation/comments, avoid incoherencies between those
and code, avoid knowledge vanishing when the coder leave your company, etc.
- and yes, an Ada compiler provides compilation/execution time checks that
other compiler can't provide, and this is in my opinion by far more usefull
than attributes. 
- etc.

Despite this, i agree with you that type compilation/execution time checks
are just the most visible consequence of the powerfull Ada typing.
When i hear an Ada programmer saying that "its primary purpose is just to
help avoid bugs", i suggest the more general "its primary purpose is to
reduce development cost", and let's go for discussion! 

-- 
Lionel Draghi