From 66c28fe2540bc6f4d4dfdaace26f1d31aebc9dc2 Mon Sep 17 00:00:00 2001
From: Tyler Young <tyoung@enbala.com>
Date: Sat, 30 Oct 2021 20:26:37 -0500
Subject: [PATCH 1/2] Just adds a note that Enum.member?/2 uses the fast :queue
 implementation (I couldn't figure out why there was no Qex.member?/2)

---
 README.md | 4 ++++
 1 file changed, 4 insertions(+)

diff --git a/README.md b/README.md
index 2dd789b..a6c3d44 100644
--- a/README.md
+++ b/README.md
@@ -46,6 +46,10 @@ iex> Enum.map Qex.new([1, 2, 3]), &(&1 + 1)
 
 iex> inspect Enum.into(1..5, %Qex{})
 "#Qex<[1, 2, 3, 4, 5]>"
+
+# Leverages :queue.member/2 under the hood for performance
+iex> Enum.member? Qex.new(1..10_000), 9_999
+true
 ```
 
 #### Create a new queue from a range

From 686309b143c233a906dcd89a7dc4e33f062f305f Mon Sep 17 00:00:00 2001
From: Tyler Young <tyoung@enbala.com>
Date: Mon, 1 Nov 2021 09:29:02 -0500
Subject: [PATCH 2/2] Make Qex.split/2 match the behavior of Enum.split/2,
 silently taking the whole queue if you ask for more elements than are
 available

---
 lib/qex.ex | 15 +++++++++++++--
 1 file changed, 13 insertions(+), 2 deletions(-)

diff --git a/lib/qex.ex b/lib/qex.ex
index c1b66e4..60465bd 100644
--- a/lib/qex.ex
+++ b/lib/qex.ex
@@ -147,7 +147,11 @@ defmodule Qex do
   end
 
   @doc """
-  Split a queue into two, the front n items are put in the first queue
+  Split a queue into two, the front n items (up to all items) are put in the first queue
+
+  Unlike :queue.split/2, which raises an ArgumentError when you ask to split more elements,
+  this matches the behavior of Enum.split/2 by silently returning the minimum of the
+  requested number of items and the complete queue.
 
       iex> q = Qex.new 1..5
       iex> {q1, q2} = Qex.split(q, 3)
@@ -155,10 +159,17 @@ defmodule Qex do
       [1, 2, 3]
       iex> Enum.to_list q2
       [4, 5]
+      iex> {q_full, q_empty} = Qex.split(q, 1_000)
+      iex> Enum.to_list q_full
+      [1, 2, 3, 4, 5]
+      iex> Enum.to_list q_empty
+      []
   """
   @spec split(t, pos_integer) :: {t, t}
   def split(%__MODULE__{data: q}, n) do
-    with {q1, q2} <- :queue.split(n, q) do
+    count = min(:queue.len(q), n)
+
+    with {q1, q2} <- :queue.split(count, q) do
       {%__MODULE__{data: q1}, %__MODULE__{data: q2}}
     end
   end