program testnums;
//{$APPTYPE CONSOLE}
uses
  Classes, SysUtils;
type
   stType = (stLite := -100, stDb, stBothLite, stBothDb); //settings
location Type
   stTypes = Array [stType] of integer;
var
 d : stType;
 s : string;
 i : integer;
begin
 writeln('');
 for i := Ord(low(stType)) to Ord(high(stType)) do
 begin
  d := stTypes[i - Ord(low(stType))];
   writestr(s,d);
   writeln(d + ' ' + IntToStr(Integer(i)));
 end;
 readln;
end.

I need to elaborate more on this code

On this line

d := stTypes[i - Ord(low(stType))];

since stTypes is an array, I expect stTypes[n], with n being 1 to 4, to retrieve an array value and as 'i - Ord(low(stType)) evaluates to integer it should compile but it generates an error.

What would be the correct way?

2010/9/12 Frank Church :

I think the array and enum are correct, but the usage isn't. I did not compile this code, but I expect a type mismatch error. You are using an integer as index in d := stTypes[i - Ord(low(stType))], but you declared stTypes an array to be indexed by stType.

2010/9/12 Frank Church :

for  d:= low(stType) to high(stType) do

>  begin >   d := stTypes[i - Ord(low(stType))];

i := stTypes[d];

Does that mean that although an enum is an ordinal type, an integer cannot be coerced into using it to index an array?

2010/9/12 Frank Church :

Does that mean that although an enum is an ordinal type, an integer cannot be coerced into using it to index an array?

IMO just cast it to the correct type (of the array index) giving the compiler a chance to accept it.