code: func ParseVersion(bts []byte) (major, minor int, ok bool) {
  	switch {
  	case bytes.Equal(bts, httpVersion11):
  		return 1, 1, true
  	case bytes.Equal(bts, httpVersion10):
  		return 1, 0, true
  	case len(bts) < 8:
  		return
  	case !bytes.Equal(bts[:5], httpVersionPrefix):
  		return
  	}
  
  	bts = bts[5:]
  
  	dot := bytes.IndexByte(bts, '.')
  	if dot == -1 {
  		return
  	}
  	major, ok = IntFromASCII(bts[:dot])
  	if !ok {
  		return
  	}
  	minor, ok = IntFromASCII(bts[dot+1:])
  	if !ok {
  		return
  	}
  
  	return major, minor, true
  }
docs: // ParseVersion parses major and minor version of HTTP protocol.
  // It returns parsed values and true if parse is ok.