Re: Real Time IO routines

[Adam Beneschan <adam@irvine.com>]

On Oct 29, 9:40 am, Robert A Duff <bobd...@shell01.TheWorld.com>
wrote:
> Adam Beneschan <a...@irvine.com> writes:
> > ... The semantics and result of 'Image are
> > well-defined by the language.  If those semantics are acceptable for a
> > particular use, then there's nothing wrong with using 'Image (unless
> > there's an issue with using a secondary stack as Ludovic mentioned).
>
> True.  But it's pretty annoying that:
>
> 'Image of integers includes an unwanted leading space.
>
> 'Image does not provide the formatting control that Text_IO does.
>
> You have to include the name of the type in the code.
>
> 'Image of enumeration literals does not print what appears in the source
> code -- it converts to ALL_CAPS.

I agree with all of those.  Nevertheless, as far as #1, #2, and #4 are
concerned, the result is still acceptable in some instances, and the
fact that it would not be good enough in some cases isn't any
particular reason to decree that it should never ever ever be used.
As for #1, I've often written my own function that declares a string S
whose value is 'Image and then returns S(S'First+1..S'Last) to get rid
of the leading space---this was before Trim functions became available
in Ada 95.  It's still more convenient than instantiating Integer_IO,
or writing your own function that uses division and "mod".  I believe
GNAT does have an 'Img attribute that can be applied to an object
(although I assume you still need 'Image for certain types of
expressions that are not valid attribute prefixes).  I don't know
whether this was ever proposed as a language addition, and if so why
it was rejected.

                        -- Adam