What type has a variable containing a range to be?

Question

A for loop can be done in Ada using a range with a start and an end point:

for I in 0..10 loop
(...)
end loop;

I know, it's possible doing the for loop using two variables describing the range:

for I in range_start..range_end loop
(...)
end loop;

Is it also possible to store the range in one variable?, like:

for I in my_range loop
(...)
end loop;

Which type has the variable *my_range* to be?

Edit: Let's say I want to use this variable as a parameter in a subprogram: So the subprogram has this loop which iterates over the range. I'd rather use two variables describing the range instead of using generics, because generics would cause in higher effort. But I think using one variable describing the range would cause in a higher readability, that's why I'm asking that question.

Answer 1

If your variable is an array, then you can iterate over its range via:

for I in Arr_Var'Range loop
   ...
end loop;

If you're interested in iterating over the elements of a container, e.g. array, vector, map, etc., and don't care about the index, you can use generalized looping (Ada 2012 only):

for Elem of Container loop
   ...
end loop;

Answer 2

Use a range type, something along these lines:

type Range_Type is range -5 .. 10;
...
for A in Range_Type loop

See the complete example in here.