Re: Ada noob here! Is Ada widely used?

["Dmitry A. Kazakov" <mailbox@dmitry-kazakov.de>]

On Wed, 26 May 2010 11:58:39 +0200, Georg Bauhaus wrote:

> A database language may be compiled by itself if the program text
> is suitably stored?

I think that is likely possible. Interestingly relational "languages" are
usually non Turing-complete. My wild guess is that it is the conversions to
a relational representation of the source code and the conversion of the
intermediate "relational" code to the machine code, which were impossible
to accomplish. No matter how trivial they might be in a language like Ada.

> Notably, a compiler has tables, relational databases have tables;
> when a compiler establishes a hierarchy (a tree), a hierachical
> database does, too, a relational database uses ... relations.

Any directed graph is a binary relation. So it is not an existential
problem, but it is a huge practical problem, because relational
representation are extremely poor with handling trees.

> Surely the "source text" will be easily processed if it reflects
> the structural properties of the database---if it is stored as
> relations. For example, when an Ada compiler marks a block such as
> a loop with a name written by the programmer, or with an ad-hoc
> name that it creates itself, then a database table of loops can
> have those names, too. (And they would serve in unique keys.)
> Similarly, the database can establish a "byte code table" for
> executing a list of CRUD instructions...
> 
> Hmm... It might in fact be interesting to store program information
> in tables.  It is then possible to perform queries like "give me all
> loops involving variables of a type in T'Class." ...

Due to total lack of abstractness relational representations require heavy
flattening, down to the lowest level. So it would be "give me the first
quark of the loop." Not very helpful.

-- 
Regards,
Dmitry A. Kazakov
http://www.dmitry-kazakov.de