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The break statement
Sometimes, it is convenient to stop the loop repetition inside the loop when a certain condition is reached. This can be done with the break statement, which is as follows:
a = 10; b = 150 while a < b # process(a) println(a) global a += 1 if a >= 50
break
end end
This prints out the numbers 10 to 49, and then exits the loop when break is encountered. The following is an idiom that is often used; how to search for a given element in an array, and stop when we have found it:
arr = rand(1:10, 10) println(arr) # get the index of search in an array arr: searched = 4 for (ix, curr) in enumerate(arr) if curr == searched println("The searched element $searched occurs on index $ix") break end end
A possible output might be as follows:
[8,4,3,6,3,5,4,4,6,6] The searched element 4 occurs on index 2
The break statement can be used in for loops as well as in while loops. It is, of course, mandatory in a while true...end loop.