There's a disconnect between the function definition and the
datastructures used by the caller.
Either fix the data structure:
(def args [:bar 2 :baz [:quux]])
then use apply
Or change the function definition to take a map:
(defn foo [x {:keys [bar baz]}]
...)
On Jun 16, 4:00 pm, Brian Carper <briancar...@gmail.com> wrote:
> Given:
>
> (defn foo [x & {:as args}] [x args])
> (foo 1 :bar 2 :baz [:quux])
> => [1 {:bar 2, :baz [:quux]}]
>
> If I have those rest-arguments already in a map, what's the most
> elegant way to call foo with them?
>
> (def args {:bar 2 :baz [:quux]})
> (foo 1 ?????)
>
> I feel like I may be missing some simple way of doing it. I find
> myself needing to do this pretty often, for example any time I have a
> chain of functions calling each other that all take keyword arguments
> on the end.
>
> (apply foo 1 (apply concat (seq args))) works, but that's awfully
> nasty. So this is what I've been doing:
>
> (defmacro apply* [& args]
> `(apply ~@(butlast args) (apply concat (seq ~(last args)))))
>
> (apply* foo 1 args)
> => [1 {:bar 2, :baz [:quux]}]
>
> Kind of hacky though. Is there a better/shorter/builtin way?
>
> I can go back to using [x & args] in the function signature and (apply
> hash-map args) in the function body, but I love having the keyword
> destructuring in the function signature, since the user can see which
> keys are valid to pass in, whenever I use {:keys [...]}.
>
> Thanks
> --Brian
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