From 2e2f81d9c55228473973b4d76e2a243be3b024c7 Mon Sep 17 00:00:00 2001
From: James Harton <james@automat.nz>
Date: Wed, 11 Oct 2017 18:26:19 +1300
Subject: [PATCH] Add basic docs to the readme.

---
 README.md        | 20 ++++++++++++++++++++
 lib/ip/prefix.ex |  6 ++++++
 2 files changed, 26 insertions(+)

diff --git a/README.md b/README.md
index 4fe9728..2b1febd 100644
--- a/README.md
+++ b/README.md
@@ -1,5 +1,8 @@
 # IP
 
+[![pipeline status](https://gitlab.com/jimsy/ip/badges/master/pipeline.svg)](https://gitlab.com/jimsy/ip/commits/master)
+[![Hex.pm](https://img.shields.io/hexpm/v/ip.svg)](https://hex.pm/packages/ip)
+
 IP, IP, Ooray! Simple IP Address representations.
 
 ## Installation
@@ -15,6 +18,23 @@ def deps do
 end
 ```
 
+## Usage
+
+`ip` provides representations for IP addresses and subnets for Elixir with a bunch of helpful stuff tacked on the side.
+
+    iex> "192.0.2.1"
+    ...> |> IP.Address.from_string!
+    #IP.Address<192.0.2.1 DOCUMENTATION>
+
+    iex> "2001:db8::"
+    ...> |> IP.Address.from_string!
+    #IP.Address<2001:db8:: DOCUMENTATION>
+
+    iex> outside = IP.Prefix.from_string!("2001:db8::/64")
+    ...> inside  = IP.Prefix.eui_64(outside, "60:f8:1d:ad:d8:90")
+    ...> IP.Prefix.contains_address?(outside, inside)
+    true
+
 Documentation can be generated with [ExDoc](https://github.com/elixir-lang/ex_doc)
 and published on [HexDocs](https://hexdocs.pm). Once published, the docs can
 be found at [https://hexdocs.pm/ip](https://hexdocs.pm/ip).
diff --git a/lib/ip/prefix.ex b/lib/ip/prefix.ex
index a3bd403..9caec7e 100644
--- a/lib/ip/prefix.ex
+++ b/lib/ip/prefix.ex
@@ -273,6 +273,12 @@ defmodule IP.Prefix do
       iex> IP.Prefix.from_string!("2001:db8::/64")
       ...> |> IP.Prefix.contains_address?(IP.Address.from_string!("2001:db8:1::1"))
       false
+
+      iex> outside = IP.Prefix.from_string!("2001:db8::/64")
+      ...> inside  = IP.Prefix.eui_64(outside, "60:f8:1d:ad:d8:90")
+      ...> IP.Prefix.contains_address?(outside, inside)
+      true
+
   """
   def contains_address?(%Prefix{address: %Address{address: addr0, version: 4}, mask: mask} = _prefix,
                         %Address{address: addr1, version: 4} = _address)