func fitsInBase256(n int, x int64) bool {
	binBits := uint(n-1) * 8
	return n >= 9 || (x >= -1<<binBits && x < 1<<binBits)
}

// parseNumeric parses the input as being encoded in either base-256 or octal.
// This function may return negative numbers.
// If parsing fails or an integer overflow occurs, err will be set.
func (p *parser) parseNumeric(b []byte) int64 {
	// Check for base-256 (binary) format first.