Re: Question from newbie

[Cecilia Chew <cecilia@nowhere.com>]

Hi all,
I'm an Ada learner and under a supervisor. This is one of my task during 
  learning period. From group comments that had provided, I did some 
amendments but the program still have errors. I wonder what to do.
Below is after amendments program :

===========================================================================
with Ada.Text_Io, Ada.Integer_Text_Io;
use Ada.Text_Io, Ada.Integer_Text_io;

procedure Sort is
    subtype Index is Integer range 1 .. 10;
    subtype Char is Character range 'a' .. 'z';
    type Str is array (Index) of Char;
    procedure Ascending (Left : in out Character; Right : in out 
Character);

    procedure Ascending (Left : in out Character; Right : in out 
Character) is

       Temp : Character;
    begin
       if Left > Right then
          Temp := Left;
          Left := Right;
          Right := Temp;
       end if;
    end Ascending;

    Num : Index;
    Input : Str;

begin
    Put ("Please enter the number of character : ");
    Get (Num);
    Ada.Text_Io.Skip_Line;
    New_Line;
    if Num not in Index then
       Put ("Please enter 1 to 10 characters only!");
    else
       Put ("Please enter" & Integer'Image(Num) & " characters : ");
       for Character_number in Index'First .. Num loop
	 Get (Input(Character_number));
	 for Character_Number in 1 .. num loop
	    Ascending (Left => Input(Character_Number),
	       Right => Input(Character_Number + 1));
	    Input(Num) := Input (Character_Number);
	 end loop;
	  Put (Input (Num));
       end loop;
     end if;
end Sort;
===============================================================================
This program could get user input characters but not the specified x 
character and any range of characters will occurred error as below.

    raised CONSTRAINT_ERROR : sort.adb:36 range check failed

where is the problem?

By the way, thanks the comments from Luke Guest, Jacob Sparre Andersen 
and Preben Randhol.



Preben Randhol wrote:
> On 2004-02-16, Cecilia Chew <cecilia@nowhere.com> wrote:
> 
>>Hi all,
>>I'm still in learning Ada. However, there were something missing in 
>>coding. Could someone point out my problems. Just take an example, i'm 
>>now doing a program that ask user input x characters and program will 
>>sort the user's input into ascending order. The is below:
> 
> 
> Before helping two questions:
> 
> 1. Is this homework?
> 2. Why do you do this: type Str is array (Index) of Char; 
> 
> 
> 
> 


-- 
Cecilia Chew
c e c i l i a <AT> g r e e n l i m e . c o m