added recursive when-let that supports multiple bindings

Author: source-c

src-clj/libmisc_clj/misc.clj

@@ -230,3 +230,10 @@
   (if (string? s)
     (-> s .trim .isEmpty not)
     false))
+
+(defmacro ^:private when-let*
+  ([bindings & body]
+   (if (seq bindings)
+     `(when-let [~(first bindings) ~(second bindings)]
+        (when-let* ~(drop 2 bindings) ~@body))
+     `(do ~@body))))