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Date: Sat, 30 Mar 2019 14:45:41 -0700 (PDT)
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Subject: Re: type definition for an integer with discrete range
From: John Perry <john.perry@usm.edu>
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Xref: reader01.eternal-september.org comp.lang.ada:56019
Date: 2019-03-30T14:45:41-07:00
List-Id: <comp.lang.ada>

You wanted a compile-time error; would a warning do? I only have it from -20 to 20 for the sake of time & space, but a Static_Predicate does the trick.

{{{
pragma Assertion_Policy(Check);

procedure Main is

  subtype Number is Integer with Static_Predicate =>
      Number in -20 | -15 | -10 | -5 | 0 | 5 | 10 | 15 | 20;
  
  A, B: Number;
  
begin
  A := 10;
  B := 12;
end Main;
}}}