// filename:line:column: message
func (err Error) Error() string {
	return fmt.Sprintf("%s: %s", err.Pos, err.Msg)
}

// FullError returns an error string like Error, buy it may contain
// type-checker internal details such as subscript indices for type
// parameters and more. Useful for debugging.
func (err Error) FullError() string {
	return fmt.Sprintf("%s: %s", err.Pos, err.Full)
}