From 210e103791f52878a7e7321bee6a965ca7f61d3f Mon Sep 17 00:00:00 2001
From: Justin Lin <justin.sdk@gmail.com>
Date: Fri, 5 Mar 2021 08:59:37 +0800
Subject: [PATCH] add find_index

---
 src/util/find_index.scad | 5 +++++
 1 file changed, 5 insertions(+)
 create mode 100644 src/util/find_index.scad

diff --git a/src/util/find_index.scad b/src/util/find_index.scad
new file mode 100644
index 00000000..5c102f96
--- /dev/null
+++ b/src/util/find_index.scad
@@ -0,0 +1,5 @@
+function find_index(lt, test) = _find_index(lt, test, len(lt));
+
+function _find_index(lt, test, leng, i = 0) =
+    i == leng ? -1 :
+    test(lt[i]) ? i : _find_index(lt, test, leng, i + 1);
\ No newline at end of file