From c75938bef9e428c41c74738281b1a9eb81c705f7 Mon Sep 17 00:00:00 2001
From: "kepler155c@gmail.com" <kepler155c@gmail.com>
Date: Wed, 24 Oct 2018 19:13:05 -0400
Subject: [PATCH] prune method in utils

---
 sys/apis/util.lua | 14 ++++++++++++++
 1 file changed, 14 insertions(+)

diff --git a/sys/apis/util.lua b/sys/apis/util.lua
index 3529583..33344fa 100644
--- a/sys/apis/util.lua
+++ b/sys/apis/util.lua
@@ -172,6 +172,20 @@ function Util.deepMerge(obj, args)
 	end
 end
 
+-- remove table entries if passed function returns false
+function Util.prune(t, fn)
+	for _,k in pairs(Util.keys(t)) do
+		local v = t[k]
+		if type(v) == 'table' then
+			t[k] = Util.prune(v, fn)
+		end
+		if not fn(t[k]) then
+			t[k] = nil
+		end
+	end
+	return t
+end
+
 function Util.transpose(t)
 	local tt = { }
 	for k,v in pairs(t) do