Re: How can i print the element poped from a generic STACK

[steve.folly@rdel.co.uk (Steve Folly)]

On Tue, 07 Nov 2000 21:43:04 +0800, jordan <huikeith@hotmail.com>
wrote:

>Dear all,
>i want to ask that how can i print the element poped from a generic
>STACK.
>i have write the following code:
>=====================================================
>with TEXT_IO;
>use TEXT_IO;
>
>procedure sample is
>
>generic
> SIZE : POSITIVE;
> type ITEM is private;
>package STACK is
> procedure PUSH(E : in ITEM);
> procedure POP (E : out ITEM);
>end STACK;
>
>package body STACK is
> type TABLE is array (POSITIVE range <>) of ITEM;
> SPACE : TABLE(1..SIZE);
> INDEX : NATURAL := 0;
>
> procedure PUSH(E : in ITEM) is
> begin
>  INDEX := INDEX + 1;
>  SPACE(INDEX) := E;
> end PUSH;
>
> procedure POP(E : out ITEM) is
> begin
>  E := SPACE(INDEX);
>  INDEX := INDEX - 1;
> end POP;
>end STACK;
>
> package stackOfInt is new STACK(100, INTEGER);
> use stackOfInt;
>
> package INT_IO is new TEXT_IO.INTEGER_IO(INTEGER);
> use INT_IO;
>
> i : Integer;
>
>begin
>
>
> stackOfInt.push(20);
>
> Put(stackOfInt.pop(i));            <------------- error!!!
>
>end sample;
>
>==============================================
>i want to print the element of integer 20 on the screen, how can i do??
>is my implementation wrong???
>


What was the error message? Usually these are very informative and in
this case will probably indicate exactly what the problem is.


-- 
Regards,
Steve Folly.