PR 23046. Folding predicates involving TYPE_MAX_VALUE/TYPE_MIN_VALUE (Ada RFC)

[Richard Kenner]

     This is simply not true for Ada.  Look at the definition of the 'Valid
     attribute in the standard:

       3. X'Valid

          Yields True if and only if the object denoted by X is normal
          and has a valid representation. The value of this attribute
          is of the predefined type Boolean.

Right.  That says what a "valid representation" is.  Except for the
result of an unchecked_conversion being given as the operand of 'Valid,
any other value in that type is erroneous.

    If your claim were true, 'Valid could never return False for
    enumeration types.

I think you misunderstand what 'Valid is.  It tests for objects being *in
the type*.  If the type were in fact the full range, then 'Valid would
always return True.