code: func _int64(i interface{}) (int64, bool) {
  
  	switch v := i.(type) {
  
  	case int:
  		return int64(v), true
  	case int8:
  		return int64(v), true
  	case int16:
  		return int64(v), true
  	case int32:
  		return int64(v), true
  	case int64:
  		return v, true
  	case uint:
  		return int64(v), true
  	case uint8:
  		return int64(v), true
  	case uint16:
  		return int64(v), true
  	case uint32:
  		return int64(v), true
  	case uint64:
  		return int64(v), true
  	}
  
  	return 0, false
  }
docs: // _int64 converts an interface{} to an int64 if its native type is
  // a integer (whether 8, 16, 32 or 64 bits, rune or byte).