From f7d0383919e8fe2cabf87cf89ee1d68a87a5c100 Mon Sep 17 00:00:00 2001
From: Andrey Antukh <niwi@niwi.nz>
Date: Mon, 15 Mar 2021 08:38:01 +0100
Subject: [PATCH] :zap: Improve performance of enumerate data helper.

---
 common/app/common/data.cljc | 9 ++++-----
 1 file changed, 4 insertions(+), 5 deletions(-)

diff --git a/common/app/common/data.cljc b/common/app/common/data.cljc
index bc3d14dba..26722cf75 100644
--- a/common/app/common/data.cljc
+++ b/common/app/common/data.cljc
@@ -42,7 +42,6 @@
   ([a b & rest]
    (reduce deep-merge a (cons b rest))))
 
-
 ;;;;;;;;;;;;;;;;;;;;;;;;;;;;;;;;;;;;;;;;;;;;;;;;;;;;;;;;;;;;;;;;;;
 ;; Data Structures Manipulation
 ;;;;;;;;;;;;;;;;;;;;;;;;;;;;;;;;;;;;;;;;;;;;;;;;;;;;;;;;;;;;;;;;;;
@@ -70,14 +69,14 @@
 (defn enumerate
   ([items] (enumerate items 0))
   ([items start]
-   (loop [idx start
+   (loop [idx   start
           items items
-          res []]
+          res   (transient [])]
      (if (empty? items)
-       res
+       (persistent! res)
        (recur (inc idx)
               (rest items)
-              (conj res [idx (first items)]))))))
+              (conj! res [idx (first items)]))))))
 
 (defn seek
   ([pred coll]