Julia has a for
loop for iterating over a collection or repeating some code a certain number of times. You can use a while
loop when the repetition depends on a condition and you can influence the execution of both loops through break
and continue
.
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...