Two 'Output questions

["Alex R. Mosteo" <devnull@mailinator.com>]

Hello everybody,

a) Is there any guarantee that 'Output is implemented like...?

    1. Write bounds/Tag
    2. Call to 'Write

I see that the containers provided with gnat gap 2005 have 'write 
redefined but not 'output. While I don't see reasons to use 'output on 
definite types (?), I'm guessing gnat does so because of a). I don't see 
any explanation in the RM, so if I'm right it may be still 
gnat-dependent. I suppose it's handy too to not have to redefine both 
'Output and 'Write when the latter is enough.

b) Is there any way to call the default 'Output attribute once you have 
redefined it? The reason for this is that I have a variant record in 
which just one of the variations needs special treatment... I have ideas 
for workarounds but I'm now just curious.

Thanks!