Re: C++ STL Components and Ada

[Brian Rogoff <bpr@shell5.ba.best.com>]

On Mon, 16 Jul 2001, James Rogers wrote:
> Occasionally I read questions from Ada newbies about the presence of
> Ada equivalents to the C++ STL. 
> 
> After many years of reading about and hearing from C++ programmers that
> the STL is the best thing since the invention of fire, I decided to
> look into exactly what the STL is. Ok, I took a little longer than 
> others :-).

The important thing you seem to be missing in your post is the presence of 
an ancillary type called iterators which are defined over the containers
and abstract the traversal so that algorithms are decoupled from
containers. You can do this in Ada too, but it's notationally a bit nicer
in C++ since the iterators over the commonest sequences map directly to
pointers.

I wouldn't say they're the best thing since the invention of fire, but C++
templates allow all sorts of interesting things, almost like macros, but
linked with the type system. They provide a crude form of parametric
polymorphism which doesn't have the overhead associated with typical
implementations of polymorphic languages. I can easily imagine an Ada-like
language which steals some nice aspects of C++ templates. 

-- Brian