[fpc-pascal] Strings

[Marco van de Voort]

In our previous episode, Carsten Bager said:
> Function Sum(p:pointer; len:LongInt):LongInt;
> Type
>   a_typ=array[0..pred(maxLongInt)] of byte;
>   a=^a_typ;
> var
>   i:LongInt;
> Begin
>   result:=0;
>   for i:=0 to len do
>     result:=result+a(p)^[i];
> End;

0..len is len+1 items.
 
> 
> Procedure test;
> Var
>   s:ansistring;
>   i:integer;
> Begin
>   s:='Something';
>   for i:=0 to 100000 do
>     s:=s+'Test';
>   if Sum(@s[1],length(s)) = 0 then

s[1] length(s) implies "lenght(s)" items. IOW the sum routine also
adds/accesses the final zero.