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From: =?utf-8?Q?Yannick_Duch=C3=AAne_=28Hibou57?=
 =?utf-8?Q?=29?=
 <yannick_duchene@yahoo.fr>
Newsgroups: comp.lang.ada
Subject: Discriminated records are not the most efficient, but ...
Date: Sat, 21 Aug 2010 23:18:35 +0200
Organization: Ada At Home
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Date: 2010-08-21T23:18:35+02:00
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Discriminated records are not the most efficient, but ... other ways to =
do  =

are likely to be turned into program logic errors.

Fully agree with this (do not like the technique of returning a special =
 =

value to indicate a state, which is a common practice with YouKnowWho).

Here is precisely a quote in this area:
> Often these tags are folded into the type as "reserved values",
> and their occurrence is not consistently checked: this is a fairly
> common source of programming errors
http://en.wikipedia.org/wiki/Tagged_union
(in =E2=80=9CAdvantages and disadvantages=E2=80=9D)

Well, this efficiency leak should at least be really weighted (heavy in =
 =

this/that case ? not heavy ?) instead of supposed by reflex.

This may be a good =E2=80=9CWarning: suspicious design=E2=80=9D topic to=
 check for  =

compilers, but I do not see a way how a compilers could determine such a=
  =

suspicious design is in use (honestly, I have an idea, but prefer not to=
  =

talk about it, because this would requires a bloat in the language).

This is an example where, while Ada help, sometime it needs your help in=
  =

return.