Re: Array slices and types

[stefan-lucks@see-the.signature]

On Wed, 20 Aug 2008, Maciej Sobczak wrote:

> Consider this:
> 
>    type Name is new String (1 .. 10);
> 
>    N : Name;
> 
>    Some_String : String := "abc";
> 
> How can I assign Some_String to the beginning slice (ie. to the first
> three characters) of N?

Some_String does always contain exactly ten characters, no more, no less.

But you can assign the first three characters of Some_String to name:

     N(1 .. 3) := Some_String;

> Everything that I can think of (short of copying characters
> individually) hits the type compatibility problem.

Here is a completely compilable example:

with Ada.Text_IO;

procedure Slice is
   S: String(1 .. 3);
   T: String(1 .. 5) := (others => '*');
   U: String(1 .. 9) := (others => '-');
begin
   S := T(1 .. 3);
   U(1 .. 5) := T;
   Ada.Text_IO.Put_Line(S & "|" & T & "|" & U);
end Slice;

As expected, the output is a line with the string "***|*****|*****----".



-- 
------ Stefan Lucks   --  Bauhaus-University Weimar  --   Germany  ------
               Stefan dot Lucks at uni minus weimar dot de
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