condas-> - A Clojure macro combining cond-> and as-> to give more flexibility in the test and step forms

condas.clj

(defmacro condas->
  "A mixture of cond-> and as-> allowing more flexibility in the test and step forms"
  [expr name & clauses]
  (assert (even? (count clauses)))
  (let [pstep (fn [[test step]] `(if ~test ~step ~name))]
    `(let [~name ~expr
           ~@(interleave (repeat name) (map pstep (partition 2 clauses)))]
       ~name)))

usage.clj

user> (condas-> {} arg
                (empty? arg) (assoc arg :foo :bar)
   
                (:foo arg)   (assoc arg :baz :buzz)

                (:foos arg)  (assoc arg :ball true))

{:baz :buzz, :foo :bar}
                   
user> (condas-> {:foos true} arg
                (empty? arg) (assoc arg :foo :bar)
                
                (:foo arg)   (assoc arg :baz :buzz)
                
                (:foos arg)  (assoc arg :ball true))

{:ball true, :foos true}

user>