when-let

macro

since v0.0-927

imported clojure.core/when-let

Edit

---

Details:

---

See Also:

• if-let
• when
• when-not
• if
• when-first

---

Source docstring:

bindings => binding-form test

When test is true, evaluates body with binding-form bound to the value of test

(defmacro when-let
  {:added "1.0"}
  [bindings & body]
  (assert-args
     (vector? bindings) "a vector for its binding"
     (= 2 (count bindings)) "exactly 2 forms in binding vector")
   (let [form (bindings 0) tst (bindings 1)]
    `(let [temp# ~tst]
       (when temp#
         (let [~form temp#]
           ~@body)))))

---