Standard version or idiomatic use of (fn [f & args] (apply f args))

Question

Every so often I find myself wanting to apply a collection of functions on several collections of parameters. It\'s easy to do with map and a very simple function.

Answer 1

There isn't a funcall or equivalent function in the standard Clojure library that works exactly this way. "apply" is pretty close but needs a collection of arguments at the end rather than being purely variadic.

With this in mind, you can "cheat" with apply to make it work as follows by adding an infinite list of nils to the end (which get considered as empty sequences of additional arguments):

(map apply [- + *] [1 2 3] [1 2 3] [1 2 3] (repeat nil))
=> (-1 6 27)

Overall though, I think the sensible approach if you really want to use this function frequently is just to define it:

(defn funcall [f & ps]
  (apply f ps))

(map funcall [- + *] [1 2 3] [1 2 3] [1 2 3])
=> (-1 6 27)