Open-ended range?

General Usage
4 
for x in x1:del:x2-del

In the initial post, I should have written that that’s not a solution:

function func(x1, del, x2)
  display(collect(x1:del:x2))
  display(collect(x1:del:(x2-del)))
end
x1 = 0.0
x2 = 2.5
delx = 1.0
func(x1, del, x2)

In this case, x1:del:x2 is what I want, because all the values satisfy x < x2.

Unless you know the values of x1, x2, and del beforehand, it’s impossible to determine whether x2 or x2 - del is the right end of the UnitRange I want.