Re: New to Ada, noticing something strange.

["Jeffrey R. Carter" <spam@spam.com>]

mike.martelli@gmail.com wrote:

> 		charMap: array (Character) of Integer;

You have undefined elements of this array, and may well be referencing them. You 
should probably initialize all of them:

type Char_Mapping is array (Character) of Integer;

Char_Map : Char_Mapping :=
('0' => 0, '1' => 1, '2' => 2, ... 'F' => 15, others => -16);

> 		NumOfArgs, size, carry: Integer := 0;

By making these Integer, you're implying that negative values are meaningful. 
These should probably be Natural. Size should probably be Positive.

> 				size := Length(operand1);

Why are you using a global variable here? Especially since it doesn't seem to be 
referenced anywhere else?

> 				when others => return strChar(1);

when others =>
    return Strchar (Strchar'First);

> 			--converts all lowercase characters to uppercase

Ada.Characters.Handling.To_Upper, as you noted elsewhere.

> 				if charMap(To_String(operand1)(i)) >= charMap(charBase) then

Here you can be referencing uninitialized values of Charmap, since the program 
has no control over the arguments it receives.

> 			for i in reverse 1 .. ResultSize(operand1,operand2) loop
> 				digit := AddDigits(To_String(operand1)(i), To_String(operand2)(i));

One of these strings may be shorter than the result of Resultsize, and when you 
try to index it with that value (first time through the loop), this should raise 
Constraint_Error.

So, what inputs did you run this with, and what output did you obtain?

-- 
Jeff Carter
"There's no messiah here. There's a mess all right, but no messiah."
Monty Python's Life of Brian
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