title: Go--no buildable Go source file in
body: <p>everyone. I have a problem with golang 's build.</p>
  
  <p>The details:</p>
  
  <p>I have a folder named "12" and creating a go source file named 12_test.go. Codes are below:</p>
  
  <pre><code>package main
  
  import "fmt"
  
  func main() {
      fmt.Println("Hello world")
  }
  </code></pre>
  
  <p>.Then typing "go build 12_test.go". Something going wrong:</p>
  
  <pre><code>"go build command-line-arguments: no buildable Go source files in D:\12"
  </code></pre>
  
  <p>So,Could someone tell me why? Thanks and apology for my poor English.</p>