You can use arrays as if they were individual operands, and it will expand out the loop and apply the expression to all the values (and can use optimization/vector tricks if posssible).

e.g.:

arr1[] += arr2[] / 10.0 + 5;

TBH, I don't use this feature much, because I work with ranges more than arrays, which do not have this ability. This feature predates ranges (and the std.algorithm.map function, which can do what you say as well).

Well you can also just call .map if you want. The nice thing about the [] operation is the compiler can optimize it more heavily since it is restricted to simpler instructions.