Re: Two ideas for the next Ada standard

[ica2ph@alpha1.csv.ica.uni-stuttgart.de (Peter Hermann)]

Are there proposals for the project name of the new standard
similar to Ada9X, such as Ada200X, Ada2000, Ada0X, etc. ?
I am expecting the new standard will come out in 2005
with a much smaller delta as it was from 83 to 95.

Van Snyder (vsnyder@math.jpl.nasa.gov) wrote:
: 1.  Allow the "mode" of an "access to procedure" or "access to function"
:     formal argument to be "limited".  Interpret this to mean "you can only
:     use this argument to access the subprogram, or pass it as an actual
:     argument to a formal argument of `limited' mode."  This would prevent
:     one from storing the "pointer" into an "access to procedure" variable,
:     and thereby allow safely passing internal procedures as actual arguments.

In Ada95, I would help myself (if really needed) by setting the internal
state of the calling environment such that an inexpected call from
outside would report or raise an exception.

: 2.  Allow an "out" "mode" for variables in specification parts, or fields
:     in records.  The interpretation is that any one can read the variables,
:     but only procedures in (or the initialization part of) the body of the
:     package can write them, or pass them to other than "in" mode formal
:     arguments in different packages.  Given this, one can safely expose
:     variables containing values one wishes to expose, but to which one does
:     not want to permit willy-nilly changes, without the need to write a
:     one-line function.

"out" is not (yet ;-) my taste. I see the designers ponder over
syntactic optima, e.g. "half constant" :-) , "not constant"
within the body in order to cancel a constant in the spec,
"protected", "half private" :-) , "read_only", or last but not least
"out". The problem with out is the perspective of view :-(  .
Certainly it is a good idea to use existing keywords.

I welcome ideas for the new standard which really should be gathered
somewhere. but where? The AALC mechanism was a sponsored activity, AFAIK.

--
Peter Hermann  Tel:+49-711-685-3611 Fax:3758 ph@csv.ica.uni-stuttgart.de
Pfaffenwaldring 27, 70569 Stuttgart Uni Computeranwendungen
Team Ada: "C'mon people let the world begin" (Paul McCartney)