Re: Design of Ada.Strings.Bounded

[mheaney@ni.net (Matthew Heaney)]

In article <5q4mel$16r$1@goanna.cs.rmit.edu.au>, Dale Stanbrough
<dale@goanna.cs.rmit.EDU.AU> wrote:

>After contemplating how i would use Ada.Strings.Bounded, i wondered about
>the decisions that were made when it was designed. 
>
>If I use it in a package, and want to add any additional features, or
>use it as a parameter type
>
>e.g. 
>        function Check_Spelling (Item : Bounded_80) return Boolean;
>
>then this is rather unfortunate when i want to check the spelling 
>of an item in a Bounded_81 string. This is exactly the same problem
>that we had in Pascal, that unconstrained types in Ada solved.

Declare your subprogram as a generic, and import the instantiation of 
Generic_Bounded_Length:

generic
   with package Bounded_Strings is
      new Ada.Strings.Bounded.Generic_Bounded_Length (<>);
   use Bounded_Strings;
function Generic_Check_Spelling (Item : Bounded_String) return Boolean;

QED.

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Matthew Heaney
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