README.md

clj-with

Macro inspired by Elixir's with statement

Macro

Chain pattern matching clauses, using clojure.core.match/match. Takes a vector of bindings to match, a body, and optionally an :otherwise keyword followed by list of clauses to match in case of failure. Pattern matches each bind and if all clauses match, the body is executed returning its result. Otherwise the chain is aborted and the non-matched value is matched against the optional :else clauses, if provided. Raises java.lang.IllegalArgumentException if none of the clauses match, just as clojure.core.match/match.

Example:

(defn f1 [] [:ok 10 20])
(defn f2 [k] [:ok (inc k)])
(defn produce-error [] [:error :match-error])

(with [[:ok x y] (f1)
       [:ok z] (f2 (+ x y))]
  (do (println "all clauses have matched :)")
      (* z 2))
      
  :otherwise 
  [:error err] err
  
  :else :no-match)
;=> 62

(with [[:ok x y] (f1)
       [:ok z] (produce-error)]
  (* z 2)
  
  :otherwise
  [:error err] err)
;=> :match-error

For more use cases peek at the test folder