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From: Robert Dewar <robert_dewar@my-deja.com>
Subject: Re: Subverting 'Access for Sub-programs
Date: 1999/08/05
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Date: 1999-08-05T00:00:00+00:00
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In article <7occq3$g9v$1@nnrp1.deja.com>,
  adam@irvine.com wrote:
> Was any solution like this considered, when Ada 95 was
> designed?  The inability to take an 'ACCESS of an inner
> subprogram seems like an obnoxious restriction, a step down
> from Pascal and Algol

Remember that Ada 83 was biased towards making the use of
displays efficient (this is in fact why Steelman prohibited
the language from containing subprogram pointers).

Remember that the decision not to allow pointers to nested
procedures in Ada 95 was based on implementation difficulties
with displays. You can second guess this non-technical decision
if you like, but for example, I have heard Aonix folk say that
the current Object Ada would have been significantly impacted
had the decision been made any other way.

Remember that Pascal and Algol semantics definitely IS tricky
for displays, as is well known (nearly all Pascal compilers
use static links).

So it is not clear what you are asking here?


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