title: Why can't I append string to byte slice as the Go reference specified?
body: <p>Quote from the <a href="http://golang.org/pkg/builtin/#append" rel="noreferrer">reference of <code>append</code> of Go</a></p>
  
  <blockquote>
    <p>As a special case, it is legal to append a string to a byte slice, like this:
    <br><code>slice = append([]byte("hello "), "world"...)</code></p>
  </blockquote>
  
  <p>But I find I can't do that as this snippet:</p>
  
  <pre><code>package main
  import "fmt"
  
  func main(){
      a := []byte("hello")
      s := "world"
      a = append(a, s) //*Error*: can't use s(type string) as type byte in append 
      fmt.Printf("%s",a)
  }
  </code></pre>
  
  <p>What have I done wrong?</p>