From 50254eb7f75d75d4b9380bf014418cd805ebfd67 Mon Sep 17 00:00:00 2001
From: Justin Lin <caterpillar@openhome.cc>
Date: Sun, 24 May 2020 16:24:26 +0800
Subject: [PATCH] add doc

---
 README.md         |  3 +++
 docs/lib2x-zip.md | 19 +++++++++++++++++++
 src/util/zip.scad | 12 +++++++++++-
 3 files changed, 33 insertions(+), 1 deletion(-)
 create mode 100644 docs/lib2x-zip.md

diff --git a/README.md b/README.md
index 97fdbc78..1fc9d2d6 100644
--- a/README.md
+++ b/README.md
@@ -208,6 +208,9 @@ See [examples](examples).
 
 ### Util
 - [util/sum](https://openhome.cc/eGossip/OpenSCAD/lib2x-sum.html)
+- [util/zip](https://openhome.cc/eGossip/OpenSCAD/lib2x-zip.html)
+
+----
 
 ## Bugs and Feedback
 
diff --git a/docs/lib2x-zip.md b/docs/lib2x-zip.md
new file mode 100644
index 00000000..ac11c33f
--- /dev/null
+++ b/docs/lib2x-zip.md
@@ -0,0 +1,19 @@
+# zip
+
+Make a list that aggregates elements from each of the lists. Returns a list of lists, where the i-th list contains the i-th element from each of the argument lists. The `zip` function stops when the first input list is exhausted. 
+
+**Since:** 2.4
+
+## Parameters
+
+- `lts` : a list of lists.
+
+## Examples
+
+    use <util/zip.scad>;
+
+    xs = [10, 20, 30];
+    ys = [5, 15, 25];
+    zs = [2.5, 7.5, 12.4];
+
+    assert(zip([xs, ys, zs]) == [[10, 5, 2.5], [20, 15, 7.5], [30, 25, 12.4]]);
\ No newline at end of file
diff --git a/src/util/zip.scad b/src/util/zip.scad
index 1bfc5aa6..a5255457 100644
--- a/src/util/zip.scad
+++ b/src/util/zip.scad
@@ -1,3 +1,13 @@
+/**
+* zip.scad
+*
+* @copyright Justin Lin, 2020
+* @license https://opensource.org/licenses/lgpl-3.0.html
+*
+* @see https://openhome.cc/eGossip/OpenSCAD/lib2x-zip.html
+*
+**/ 
+
 use <_impl/_zip_impl.scad>;
 
-function zip(lists) = _zipAll(lists);
\ No newline at end of file
+function zip(lts) = _zipAll(lts);
\ No newline at end of file