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Date: Tue, 30 Nov 2021 13:39:28 +0100
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Subject: Re: Empty String confusion; Positive and Natural
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Op 30-11-2021 om 9:21 schreef Simon Wright:
> ldries46 <bertus.dries@planet.nl> writes:
>
>> Empty_String : Unbounded_String := To_Unbounded_String("");
> * Given the name, you should probably declare it constant.
>
> * You don't need to initialize it, ARM 4.5(73) [1] says "If an object of
>    type Unbounded_String is not otherwise initialized, it will be
>    initialized to the same value as Null_Unbounded_String".
>
> * Ada.Strings.Unbounded.Null_Unbounded_String is a constant empty
>    string.
>
> [1] http://www.ada-auth.org/standards/rm12_w_tc1/html/RM-A-4-5.html#p73
You are right. it should be

Empty_String : constant Unbounded_String := To_Unbounded_String("");