Error checking for type incompatibility

[cptnben@gisco.net (Ben)]

Hi, 
I am new to Ada. I decided I would try to learn a new language and Ada
seemed like a fun project. I got a few books, and one of them has
challenge problem where I am supposed to do some error checking on
input. This includes checking to make sure that the input type is
correct. More specifically: the program is supposed to accept only
integer values. So I need to be able to have an error handler that
will recognize if someone tries to enter a noninteger value and ask
them to re-enter a correct value. Since this is a "challenge problem"
they are not giving me alot to work on here. I checked another book,
and it had some examples on error handling, but not at the level I
need. And neither book had any example code that was helpful.
Remember, I'm new to Ada (from the C++ world) so packages are new to
me. What do I need folks. Your help is greatly appreciated.

Thanks,
Ben