Better way to nest if-let in clojure

clojure, if-statement

Solution

I think a macro may be necessary here to create the behavior you want. I have never written one (yet) but the following representation suggests to me that this might be fairly straightforward:

(let [{:keys [a b]} m]
   (when (every? identity [a b])
      (println (str "Processing " a " and " b))))

Using the `:keys` form of destructuring binding and `every?` enables a single specification of a vector of keys to destructure and check, and the bound locals are available in a following code block.

This could be used to make a macro such as `(when-every? [keys coll] code-with-bindings)`

I may update this answer with the macro code if I can take the time to work out how to do it.

Problem

Say I have a map of this form: ``` (def m {:a "A" :b "B"}) ``` and I want to do something if `:a` and `:b` are both not nil, I can do: ``` (if-let [a (:a m)] (if-let [b (:b m)] ... etc )) ``` or ``` (if (and (:a m) (:b m)) (let [{a :a b :b} m] ... etc )) ``` or even ``` (if (every? m [:a :b]) (let [{a :a b :b} m] ... etc )) ``` Is there a neater (ie one-line) way to achieve this?

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