From b739e5f329d5d7ed3bf59ddff5328643687c10d2 Mon Sep 17 00:00:00 2001
From: Steven Degutis <steven.degutis@gmail.com>
Date: Mon, 26 Mar 2012 18:15:06 -0500
Subject: [PATCH] adding common interfaces koan

---
 about_common_interfaces.go | 32 ++++++++++++++++++++++++++++++++
 setup_koans_test.go        |  1 +
 2 files changed, 33 insertions(+)
 create mode 100644 about_common_interfaces.go

diff --git a/about_common_interfaces.go b/about_common_interfaces.go
new file mode 100644
index 0000000..80eb6b6
--- /dev/null
+++ b/about_common_interfaces.go
@@ -0,0 +1,32 @@
+package go_koans
+
+import "bytes"
+
+func aboutCommonInterfaces() {
+  {
+    in := new(bytes.Buffer)
+    in.WriteString("hello world")
+
+    out := new(bytes.Buffer)
+
+    /*
+       Your code goes here.
+       Hint, use these resources:
+
+       $ godoc -http=:8080
+       $ open http://localhost:8080/pkg/io/
+       $ open http://localhost:8080/pkg/bytes/
+    */
+
+    assert(out.String() == "hello world") // get data from the io.Reader to the io.Writer
+  }
+
+  {
+    in := new(bytes.Buffer)
+    in.WriteString("hello world")
+
+    out := new(bytes.Buffer)
+
+    assert(out.String() == "hello") // duplicate only a portion of the io.Reader
+  }
+}
diff --git a/setup_koans_test.go b/setup_koans_test.go
index 8ce24b2..461aa2d 100644
--- a/setup_koans_test.go
+++ b/setup_koans_test.go
@@ -32,6 +32,7 @@ func TestKoans(t *testing.T) {
   aboutVariadicFunctions()
   aboutFiles()
   aboutInterfaces()
+  aboutCommonInterfaces()
   aboutMaps()
   aboutPointers()
   aboutStructs()