Ok i think the issue is that you should not do that at all. You should not simulate imperative or object oriented (with mutable state) constructs in functional languages. Your example is still not good.
for x <- 0..10, do: action(x)
is what you probably should have used.
Anyway that old plain C-like for loop with starting value accumulator is something that is not really readable, and has no use in modern languages.
In ruby you have:
some_objects.each { |an_object| action(object) }
# or
for an_object in some_objects
action(an_object)
end
In python you also iterate over collection like this
for an_object in some_objects:
action(an_object)
Even in Java since Java 5 you would probably do
for(ClassName an_object : some_objects) {
action(an_object)
}
One of my most hated languages: JavaScript, has similar constructs
function callback_function(currentObject, index, array) {
action(currentObject)
}
some_objects.forEach(callback_function)
Why? Because all of those are much more readable and descriptive, then that old plain C-like for loop. Answer yourself, how often you really need that index? Don’t you really want the object that stands behind that index?
And in Elixir you have what @thousandsofthem and @jwarlander wrote. And you should be using it instead of trying to wrap some logic into totally (in Elixir) out of place C-like for loop 
