Syntax
for(iterable, body)
Iterate over each item in an iterable value.
for() takes two arguments, an iterable value such as a list or a map
(iterates over the keys of the map), and an expression to evaluate for every
item. The expression receives two bound variables _ (value) and _i (current
iteration number).
for([1, 2, 3, 4, 5], print(_));
for() returns the number of times the expression evaluated to a successful
value.
Like other looping functions for() supports break() and continue(). An
optional argument can be passed to break() or continue() to determine if the
iteration was successful.
i = for([42, 12, 56, 29], print(_i)); // 0, 1, 2, 3
i; // 4