Path: utzoo!utgpu!watmath!clyde!att!ucbvax!telesoft.UUCP!brian
From: brian@telesoft.UUCP (Brian D. Nettleton @spot)
Newsgroups: comp.lang.ada
Subject: Limited Use Clause
Message-ID: <8812060022.AA26972@ucsd.edu>
Date: 5 Dec 88 23:39:29 GMT
Sender: daemon@ucbvax.BERKELEY.EDU
Organization: The Internet
Lines: 32

Mike Glasgow of IBM asked me to post this idea here as he doesn't
have access to this network.

Mike and I discussed yet another change to Ada for Ada-9x, the
addition of a "limited" use clause.  This clause would allow
direct visibility of only the implicit infix operators of a visible part
of a particular package.  I do beleive this request does probably
fall into Stanley Allen's reference to "feature junkies" but that
still doesn't stop me.  The syntax might go something like (included
here only for example, I don't care too much about what words are
chosen):

  with xyz;
  ...
  use limited xyz;
  ...

As more of a maintainer of code than a developer (much of my work
involves porting and integrating other peoples code) I'm certainly
aware of how horrible use clauses can be when your looking at someone
else's code.  Therefore I agree with the coding standard Mike's project at
IBM is using which does not permit any use clauses.  I also agree with
Mike that the restriction causes unnecessary problems when you define
a derived type of say integer and then using this derived type and it's 
associated implied operators is a real pain with lots of extra "noise" 
code (i.e. renaming "=" and "+" over and over again even though they have 
the "standard" Ada definition).

Brian Nettleton
TeleSoft

- These ideas are my own and not necessarily that of my employer, etc...