From 2598fb2be2edbf4aca93ec4670e68c387c55b565 Mon Sep 17 00:00:00 2001
From: Justin Lin <caterpillar@openhome.cc>
Date: Wed, 26 Feb 2020 12:32:26 +0800
Subject: [PATCH] add sum.scad

---
 src/experimental/_impl/_sum_impl.scad | 2 ++
 src/experimental/sum.scad             | 3 +++
 2 files changed, 5 insertions(+)
 create mode 100644 src/experimental/_impl/_sum_impl.scad
 create mode 100644 src/experimental/sum.scad

diff --git a/src/experimental/_impl/_sum_impl.scad b/src/experimental/_impl/_sum_impl.scad
new file mode 100644
index 00000000..2c2bc47b
--- /dev/null
+++ b/src/experimental/_impl/_sum_impl.scad
@@ -0,0 +1,2 @@
+function _sum_impl(lt, leng, i = 0) =
+    i == leng - 1 ? lt[i] : (lt[i] + _sum_impl(lt, leng, i + 1));
diff --git a/src/experimental/sum.scad b/src/experimental/sum.scad
new file mode 100644
index 00000000..14d62e5f
--- /dev/null
+++ b/src/experimental/sum.scad
@@ -0,0 +1,3 @@
+use <experimental/_impl/_sum_impl.scad>;
+
+function sum(lt) = _sum_impl(lt, len(lt));
\ No newline at end of file