From 4355d5ae806ebbc0cdbef0b39f61330e8747df0c Mon Sep 17 00:00:00 2001
From: Andrey Antukh <niwi@niwi.nz>
Date: Tue, 29 Sep 2020 10:00:10 +0200
Subject: [PATCH] :tada: Add nil-free hashmap factory macros.

---
 common/app/common/data.cljc | 30 +++++++++++++++++++++++++++++-
 1 file changed, 29 insertions(+), 1 deletion(-)

diff --git a/common/app/common/data.cljc b/common/app/common/data.cljc
index fe84e3f83..c0033c171 100644
--- a/common/app/common/data.cljc
+++ b/common/app/common/data.cljc
@@ -6,7 +6,7 @@
 
 (ns app.common.data
   "Data manipulation and query helper functions."
-  (:refer-clojure :exclude [concat read-string])
+  (:refer-clojure :exclude [concat read-string hash-map])
   (:require [clojure.set :as set]
             [linked.set :as lks]
             #?(:cljs [cljs.reader :as r]
@@ -115,6 +115,34 @@
   [data]
   (into {} (remove (comp nil? second) data)))
 
+
+(defmacro without-nils
+  "A generic helper macro that removes nils from hash-map from
+  collection at compile time. If it is not possible (a symbol is
+  received), fallback to runtume nil removing procediment thanks to
+  `remove-nil-vals` function."
+  [param]
+  (cond
+    (symbol? param)
+    `(remove-nil-vals ~param)
+
+    (map? param)
+    `~(remove-nil-vals param)
+
+    :else
+    (throw (ex-info "Invalid arguments"
+                    {:type :internal
+                     :code :invalid-arguments}))))
+
+(defmacro hash-map
+  "A closure friendly macro for build nil-free hash-maps at compile
+  time."
+  [& kvpairs]
+  (let [data (->> (partition 2 kvpairs)
+                  (remove (comp nil? second))
+                  (mapcat identity))]
+    `(hash-map ~@data)))
+
 (defn without-keys
   "Return a map without the keys provided
   in the `keys` parameter."