You can use forM. As for why for loops are imperative or if they are... Not sure. A few thoughts come to mind: For loops dont return a value, whereas forM and

You can use forM. As for why for loops are imperative or if they are... Not sure. A few thoughts come to mind: For loops dont return a value, whereas forM and even forM_ both return values. They are normal functions rather than just control structures.