Clojurians Log v2

Is there a reason why selector returns a function?

What else could it return?

Are you looking for more of a 1-shot use?

Yes, it could take 2 arguments and return the result. Like select-keys.

((selector destructure-map-literal) data-map)

The reason it returns a function instead doing a single job is that the compiler is doing a bunch of work to make the selector, and the common case is to apply it to many pieces of data ala map, so it makes sense to do that once while making the selector function, not repeatedly in a one-shot mechanism

Sean, note that destructure-map there must be a literal

Yes, it was just easier to type that on my phone 🙂

Updated it now 🙂

What's the likelihood spec1 will see further development? Will all future focus be on spec2?

For me this would be more useful:

(defmacro select
  ([destructure-map-literal]
   (let [sel (gensym)
         miss (gensym)
         as (gensym)
         exc (gensym)
         destructure-map-literal (assoc destructure-map-literal
                                        :select sel
                                        :missing miss
                                        :as as
                                        :excess exc)]
     `(fn [data-map#]
        (let [~destructure-map-literal data-map#]
          {:select ~sel
           :missing ~miss
           :as ~as
           :excess ~exc}))))
  ([destructure-map-literal data-map]
   `((select ~destructure-map-literal) ~data-map)))

(select {:keys! [a b]})               ; a function
((select {:keys! [a b]}) {:a 4 :c 7}) ; a result
(select {:keys! [a b]} {:a 4 :c 7})   ; a result

well now you have it :)

@hbrng.computer Don't forget to add :all to that. :as does not include any defaults from :or, whereas :all does.