Re: Enum'Image (Was: Improving Ada's image)

["Alexander E. Kopilovich" <aek@VB1162.spb.edu>]

Jacob Sparre Andersen wrote:

> >   Enum'Image(My_Variable, Verbatim)
>
> Why not also allow "Upper_Case" and "Lower_Case"?

Because you always can do these conversions later in your code. Providing
all those translations in any form (attribute, "for ... use" clause or pragma)
is just a redundant feature, perhaps convenient for some relatively rare
programs but  nothing more than that. But Verbatim case is different -
you can't restore by you code an information that is already lost; so this
Verbatim just prevent loss of information, which was present in the source
code.

But even the possibility of Verbatim seems somehow doubtful because it will
slightly violate the rule of case insensitivity for names in Ada programs.
That is, with this Verbatim option the behaviour of a program can depend on
the case of the letters used inside the names in enums. One can argue that
those names in enums resemble literals and therefore the case insensitivity
rule should not be applied to them, but this is a problematic issue, I think.

And anyway, it may be practically impossible for some compilers: if a compiler 
currently translate identifiers (including those from enums) before storing
them in the symbol table then it probably would be not a small pain to change
that tactics.




Alexander Kopilovich                      aek@vib.usr.pu.ru
Saint-Petersburg
Russia