Re: Ada access vs C/C++ pointers and references

[Jim Rogers <jimmaureenrogers@worldnet.att.net>]

duggar@mit.edu (Keith H Duggar) wrote in news:b47de02.0408181427.25d82fe1
@posting.google.com:

> I'm simply asking four things.
> 
> First, is it correct to say that Ada access types ore more
> similar to C++ references (T&) than they are to C/C++
> pointers (T*) ?

Not really. C++ references are always implemented as const
pointers. Ada access types are assignable, just like C/C++
pointers.

> 
> Second, does Ada provide any facilities for direct and raw
> memory access by memory address and pointer arithmetic?

Yes, but not directly through access types. The package
System.Storage_Elements provides the ability to perform
integer arithmetic on addresses.

Note that the package contains functions for converting between
addresses and Integer_Address. This allows Ada to work correctly
on systems without linear addressing schemes, such as the old