code: func ToFloat(v interface{}) float64 {
  	switch n := v.(type) {
  	case int:
  		return float64(n)
  	case int8:
  		return float64(n)
  	case int16:
  		return float64(n)
  	case int32:
  		return float64(n)
  	case int64:
  		return float64(n)
  	case uint:
  		return float64(n)
  	case uint8:
  		return float64(n)
  	case uint16:
  		return float64(n)
  	case uint32:
  		return float64(n)
  	case uint64:
  		return float64(n)
  	case float32:
  		return float64(n)
  	case float64:
  		return n
  	default:
  		return math.NaN()
  	}
  }
docs: // ToFloat returns a float or NaN.