5 files changed, 41 insertions, 28 deletions
diff --git a/doc/progs/eff_unused1.go b/doc/progs/eff_unused1.go
new file mode 100644
index 000000000..f990a19f7
--- /dev/null
+++ b/doc/progs/eff_unused1.go
@@ -0,0 +1,18 @@
+// skip
+
+package main
+
+import (
+	"fmt"
+	"io"
+	"log"
+	"os"
+)
+
+func main() {
+	fd, err := os.Open("test.go")
+	if err != nil {
+		log.Fatal(err)
+	}
+	// TODO: use fd.
+}
diff --git a/doc/progs/eff_unused2.go b/doc/progs/eff_unused2.go
new file mode 100644
index 000000000..3e6e041c7
--- /dev/null
+++ b/doc/progs/eff_unused2.go
@@ -0,0 +1,22 @@
+// compile
+
+package main
+
+import (
+	"fmt"
+	"io"
+	"log"
+	"os"
+)
+
+var _ = fmt.Printf // For debugging; delete when done.
+var _ io.Reader    // For debugging; delete when done.
+
+func main() {
+	fd, err := os.Open("test.go")
+	if err != nil {
+		log.Fatal(err)
+	}
+	// TODO: use fd.
+	_ = fd
+}
diff --git a/doc/progs/run b/doc/progs/run
index da777f329..71759c565 100755
--- a/doc/progs/run
+++ b/doc/progs/run
@@ -16,6 +16,7 @@ effective_go="
 	eff_bytesize
 	eff_qr
 	eff_sequence
+	eff_unused2
 "
 
 error_handling="
diff --git a/doc/progs/unused1.go b/doc/progs/unused1.go
deleted file mode 100644
index 96a6d98a3..000000000
--- a/doc/progs/unused1.go
+++ /dev/null
@@ -1,12 +0,0 @@
-// skip
-
-package main
-
-import (
-	"fmt"
-	"io"
-)
-
-func main() {
-	greeting := "hello, world"
-}
diff --git a/doc/progs/unused2.go b/doc/progs/unused2.go
deleted file mode 100644
index 5c5f9d74f..000000000
--- a/doc/progs/unused2.go
+++ /dev/null
@@ -1,16 +0,0 @@
-// compile
-
-package main
-
-import (
-	"fmt"
-	"io"
-)
-
-var _ = fmt.Printf
-var _ io.Reader
-
-func main() {
-	greeting := "hello, world"
-	_ = greeting
-}