Re: Can Ada print coloured/styled text to the terminal? (ANSI escape sequences?)

["Randy Brukardt" <randy@rrsoftware.com>]

"Per Sandberg" <per.s.sandberg@bahnhof.se> wrote in message 
news:LewaD.910619$aC7.586128@fx03.fr7...
...
> I think you put the finger on the problem with time, and that is that time 
> implies change. And to require every newly written software to be 
> compatible with every previous compiler does not work since that would 
> mean freezing time. However to require new compilers to accept old code 
> (sometimes with minor modification due to new keywords for example) is 
> complete different story.

That only makes sense for code that was created to be portable.

That requires that the code was compiled on multiple Ada compilers, lest it 
depend on incorrect implementations of Ada or vendor-specific 
features/interpretations. By definition, that cannot be the case for Ada 
2012 code, since there is no other such compiler. I was only worrying about 
currently supported Ada compilers: ObjectAda (bit of Ada 2012, full Ada 
2005), Apex (full Ada 2005), Irvine (full Ada 2005), and Janus/Ada (little 
bit of everything, not a whole lot of anything :-)

The alternative is to say that every Ada compiler has to clone GNAT, 
including all of its unique (and unimplementable in other technologies) 
features like Unrestricted_Access -- rather than implement the Ada language 
as defined. In that case, there is no real point to even having an Ada 
standard or even other Ada compilers (they could never match up to the 
"original").

That's not my idea of a healthy marketplace where the best 
ideas/implementations have an opportunity to win. Nor is it practical for 
Janus/Ada: for instance, changing the definition of Integer would break 
binary compatibility for all of our customers (Sequential_IO, Direct_IO, 
Stream_IO), which isn't a reasonable thing to do. Code sharing of generics 
is not allowed in such a world (it's incompatible at the margins with GNAT), 
meaning several man-years of re-engineering (and loss of capability, too). 
And so on.

For a substantial portion of Ada users, GNAT lock-in isn't a problem. Then 
use GNATCOLL and lots of other GNAT-specific software. For people that don't 
want to be locked in, care is needed.

                                                 Randy.