Re: Ada Enumerations

[Stephen Leake <Stephen.Leake@gsfc.nasa.gov>]

Jeffrey Harris wrote:
> 
> I have created an Ada Enumeration called DataTypes, afterwards I've created a
> 'use' clause where I give each element an integer value.  The last Enumeration
> is LASTTYPE and is given a value of 100.
> 
> Now to the problem.  I'd like to be able to do something like the following..
> 
> NewLocation: Integer := DataTypes.LASTTYPE + 1;  -- Newlocation = 101

It looks like you should use an integer type for DataTypes, rather than
an enumeration type. Take a step back, and consider why you are doing
this in the first place. If you post a discription of your broader
problem, maybe we could give some better advice.

> 
> The compiler isn't letting me do this.  I've tried to use 'value, 'pos, and
> 'val to no avail, how do I convert an Ada enumerated type into an integer value?

If you really, really need to do this, GNAT provides the non-standard
attribute 'Enum_Rep, which gives you the integer you specified for the
enumeration literal. ObjectAda does not provide this attribute - I don't
know about other compilers.
You can use Unchecked_Conversion to get the same result.

> 
> Thanx... Please e-mail me at harris@pcisys.net
> 
> Jeff Harris

-- 
- Stephe