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Close #1

Author: davecheney

examples/build/README.md

@@ -388,6 +388,7 @@ type Package struct {
     IgnoredGoFiles []string // .go source files ignored for this build
     CFiles         []string // .c source files
     CXXFiles       []string // .cc, .cpp and .cxx source files
+    MFiles         []string // .m (Objective-C) source files
     HFiles         []string // .h, .hh, .hpp and .hxx source files
     SFiles         []string // .s source files
     SwigFiles      []string // .swig files

main.go

@@ -58,7 +58,7 @@ var (
 		"comment_md": comment_mdFunc,
 		"base":       path.Base,
 		"md":         mdFunc,
-		"pre":	      preFunc,
+		"pre":        preFunc,
 	}
 )
 
@@ -77,7 +77,7 @@ func mdFunc(text string) string {
 }
 
 func preFunc(text string) string {
-	return "``` go\n"+text+"\n```"
+	return "``` go\n" + text + "\n```"
 }
 
 func readTemplate(name, data string) *template.Template {
@@ -97,6 +97,11 @@ func main() {
 	flag.Usage = usage
 	flag.Parse()
 
+	// Check usage
+	if flag.NArg() == 0 {
+		usage()
+	}
+
 	// use file system of underlying OS
 	fs.Bind("/", vfs.OS(*goroot), "/", vfs.BindReplace)