We already encountered the for loop when iterating over the elements e of a collection coll (refer to the Strings and Ranges and Arrays sections in Chapter 2, Variables, Types, and Operations). This takes the general form:

# code in Chapter 4\repetitions.jl
for e in coll
   # body: process(e) executed for every element e in coll
end

Here, coll can be a range, a string, an array, or any other iterable collection (for other uses, also refer to Chapter 5, Collection Types). The variable e is not known outside the for loop. When iterating over a numeric range, often = (equal to) is used instead of in:

    for n = 1:10  
       print(x^3)  
    end

(This code can be a one-liner, but is spread over three lines for clarity...