message: from_radix_be/le for BigInt
diff: @@ -980,6 +980,46 @@ impl BigInt {
  BigInt::from_biguint(sign, BigUint::from_bytes_le(bytes))
  }
  + /// Creates and initializes a `BigInt`. Each u8 of the input slice is
  + /// interpreted as one digit of the number
  + /// and must therefore be less than `radix`.
  + ///
  + /// The bytes are in big-endian byte order.
  + /// `radix` must be in the range `2...256`.
  + ///
  + /// # Examples
  + ///
  + /// ```
  + /// use num_bigint::{BigInt, Sign};
  + ///
  + /// let inbase190 = vec![15, 33, 125, 12, 14];
  + /// let a = BigInt::from_radix_be(Sign::Minus, &inbase190, 190).unwrap();
  + /// assert_eq!(a.to_radix_be(190), (Sign:: Minus, inbase190));
  + /// ```
  + pub fn from_radix_be(sign: Sign, buf: &[u8], radix: u32) -> Option<BigInt> {
  + BigUint::from_radix_be(buf, radix).map(|u| BigInt::from_biguint(sign, u))
  + }
  +
  + /// Creates and initializes a `BigInt`. Each u8 of the input slice is
  + /// interpreted as one digit of the number
  + /// and must therefore be less than `radix`.
  + ///
  + /// The bytes are in little-endian byte order.
  + /// `radix` must be in the range `2...256`.
  + ///
  + /// # Examples
  + ///
  + /// ```
  + /// use num_bigint::{BigInt, Sign};
  + ///
  + /// let inbase190 = vec![14, 12, 125, 33, 15];
  + /// let a = BigInt::from_radix_be(Sign::Minus, &inbase190, 190).unwrap();
  + /// assert_eq!(a.to_radix_be(190), (Sign::Minus, inbase190));
  + /// ```
  + pub fn from_radix_le(sign: Sign, buf: &[u8], radix: u32) -> Option<BigInt> {
  + BigUint::from_radix_le(buf, radix).map(|u| BigInt::from_biguint(sign, u))
  + }
  +
  /// Returns the sign and the byte representation of the `BigInt` in little-endian byte order.
  ///
  /// # Examples
  