Re: 'Size hack for enumerated types

[sbelmont700@gmail.com]

On Sunday, July 6, 2014 12:16:00 PM UTC-4, Victor Porton wrote:
> 
> Your way does not work backward (K^{-1}).
> 

Sure it can, contingent on the C enum not being declared in any sort of inane manner:

subtype E is Interfaces.C.int range 1 .. 3;

K_Inv : constant array (E) of T :=
 (1 => x;
  2 => y;
  3 => z);

Of course, any number of stupid programmer tricks could have been done on the other end to put gaps in the values, have multiple elements with the same value, or even make them implementation-defined non-integer numbers, in which case all bets are off.  Though all bets are off anyway, since there is no reason to expect a C function to return a valid value in the first place.

-sb