Editing For loop (section)

===Compound for-loops===
Introduced with [[ALGOL 68]] and followed by PL/I, this allows the iteration of a loop to be compounded with a test, as in
 for i := 1 : N while A(i) > 0 do ''etc.''
That is, a value is assigned to the loop variable ''i'' and only if the ''while expression'' is '''true''' will the loop body be executed. If the result were '''false''' the for-loop's execution stops short. Granted that the loop variable's value ''is'' defined after the termination of the loop, then the above statement will find the first non-positive element in array ''A'' (and if no such, its value will be ''N + 1''), or, with suitable variations, the first non-blank character in a string, and so on.