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Newsgroups: comp.lang.ada
Date: Fri, 19 Oct 2018 10:06:54 -0700 (PDT)
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Subject: Re: A function that cannot be called?
From: AdaMagica <christ-usch.grein@t-online.de>
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Xref: reader02.eternal-september.org comp.lang.ada:54657
Date: 2018-10-19T10:06:54-07:00
List-Id: <comp.lang.ada>

I do not really understand what all this is about, but:

package What is
  type Void (<>) is private;
  function Create (Params: Some_Type) return Void is abstract;
private
  type Void is null record;  -- no values
end What;

Void has no values (hm, a null record is a value, but it's irrelevant, sinc=
e no objects exist (there is none in the private part; a body is illegal); =
no objects can be created because Create is abstract, so in effect Create d=
oes not exist - so it cannot be called.

With caveat - I didn't try to compile this.