From 74af0889b955a34b31ef2b58a2ab861d44cdf0de Mon Sep 17 00:00:00 2001
From: Adam Hathcock <adam.hathcock@autodesk.com>
Date: Mon, 3 Oct 2016 10:16:26 +0100
Subject: [PATCH] Make PpmdProperties lazy to avoid unnecessary allocations.

---
 README.md                                            | 2 +-
 src/SharpCompress/Compressors/PPMd/PpmdProperties.cs | 7 -------
 src/SharpCompress/Compressors/PPMd/PpmdVersion.cs    | 9 +++++++++
 src/SharpCompress/Writers/Zip/ZipWriter.cs           | 6 +++---
 4 files changed, 13 insertions(+), 11 deletions(-)
 create mode 100644 src/SharpCompress/Compressors/PPMd/PpmdVersion.cs

diff --git a/README.md b/README.md
index 83c2d35c..1b1ef1db 100644
--- a/README.md
+++ b/README.md
@@ -9,7 +9,7 @@ The major feature is support for non-seekable streams so large files can be proc
 ## Need Help?
 Post Issues on Github!
 
-Check the [Supported Formats](FORMATS.md) and [basic usage.](USAGE.md)
+Check the [Supported Formats](FORMATS.md) and [Basic Usage.](USAGE.md)
 
 ## A Simple Request
 
diff --git a/src/SharpCompress/Compressors/PPMd/PpmdProperties.cs b/src/SharpCompress/Compressors/PPMd/PpmdProperties.cs
index 7e02d6c0..25e90b6e 100644
--- a/src/SharpCompress/Compressors/PPMd/PpmdProperties.cs
+++ b/src/SharpCompress/Compressors/PPMd/PpmdProperties.cs
@@ -3,13 +3,6 @@ using SharpCompress.Converters;
 
 namespace SharpCompress.Compressors.PPMd
 {
-    public enum PpmdVersion
-    {
-        H,
-        H7z,
-        I1
-    }
-
     public class PpmdProperties
     {
         public PpmdVersion Version = PpmdVersion.I1;
diff --git a/src/SharpCompress/Compressors/PPMd/PpmdVersion.cs b/src/SharpCompress/Compressors/PPMd/PpmdVersion.cs
new file mode 100644
index 00000000..c4d17015
--- /dev/null
+++ b/src/SharpCompress/Compressors/PPMd/PpmdVersion.cs
@@ -0,0 +1,9 @@
+namespace SharpCompress.Compressors.PPMd
+{
+    public enum PpmdVersion
+    {
+        H,
+        H7z,
+        I1
+    }
+}
\ No newline at end of file
diff --git a/src/SharpCompress/Writers/Zip/ZipWriter.cs b/src/SharpCompress/Writers/Zip/ZipWriter.cs
index 37c216b1..f93cf3cf 100644
--- a/src/SharpCompress/Writers/Zip/ZipWriter.cs
+++ b/src/SharpCompress/Writers/Zip/ZipWriter.cs
@@ -19,7 +19,7 @@ namespace SharpCompress.Writers.Zip
     {
         private readonly CompressionType compressionType;
         private readonly CompressionLevel compressionLevel;
-        private readonly PpmdProperties ppmdProperties = new PpmdProperties(); // Caching properties to speed up PPMd
+        private readonly Lazy<PpmdProperties> ppmdProperties = new Lazy<PpmdProperties>(() => new PpmdProperties()); // Caching properties to speed up PPMd
         private readonly List<ZipCentralDirectoryEntry> entries = new List<ZipCentralDirectoryEntry>();
         private readonly string zipComment;
         private long streamPosition;
@@ -252,8 +252,8 @@ namespace SharpCompress.Writers.Zip
                     }
                     case ZipCompressionMethod.PPMd:
                     {
-                        counting.Write(writer.ppmdProperties.Properties, 0, 2);
-                        return new PpmdStream(writer.ppmdProperties, counting, true);
+                        counting.Write(writer.ppmdProperties.Value.Properties, 0, 2);
+                        return new PpmdStream(writer.ppmdProperties.Value, counting, true);
                     }
                     default:
                     {