How to use strings in Ada?

General
13

That’s not entirely true.
(Adding in your own "+" or "&" operators to the following…)

Package Pascal_String with Pure is
   Subtype Byte is Interfaces.Unsigned_8;
   Type String is private;
   -- All the manipulation functions + create.
   Function "+"( Input : Standard.String ) return String
      with Pre => Input'Length in Byte'Range;
   Function "+"(Input : String) return Standard.String;
Private

   Type String is record
      Length : Byte:= 0;
      Text   : Standard.String(1..255):= (others => ASCII.NUL);
   end record
   with Size => 256 * Byte'Size;
   -- Convert to/from Internal.String via unchecked conversion.

   Function "+"( Input : Standard.String ) return String is
   ( Length => Byte(Input'Length),
     Text   => Input & (Input'Length+1..256 => ASCII.NUL)
    );
   Function "+"(Input : String) return Standard.String is
   ( Input.Text(1..Input.Length) );
End_Pascal_String;
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