pub trait LowerHex {
// Required method
fn fmt(&self, f: &mut Formatter<'_>) -> Result<(), Error>;
}Expand description
x formatting.
The LowerHex trait should format its output as a number in hexadecimal, with a through f
in lower case.
For primitive signed integers (i8 to i128, and isize),
negative values are formatted as the two’s complement representation.
The alternate flag, #, adds a 0x in front of the output.
For more information on formatters, see the module-level documentation.
§Examples
Basic usage with i32:
let y = 42; // 42 is '2a' in hex
assert_eq!(format!("{y:x}"), "2a");
assert_eq!(format!("{y:#x}"), "0x2a");
assert_eq!(format!("{:x}", -16), "fffffff0");Implementing LowerHex on a type:
use std::fmt;
struct Length(i32);
impl fmt::LowerHex for Length {
fn fmt(&self, f: &mut fmt::Formatter<'_>) -> fmt::Result {
let val = self.0;
fmt::LowerHex::fmt(&val, f) // delegate to i32's implementation
}
}
let l = Length(9);
assert_eq!(format!("l as hex is: {l:x}"), "l as hex is: 9");
assert_eq!(format!("l as hex is: {l:#010x}"), "l as hex is: 0x00000009");Required Methods§
1.0.0 · Sourcefn fmt(&self, f: &mut Formatter<'_>) -> Result<(), Error>
fn fmt(&self, f: &mut Formatter<'_>) -> Result<(), Error>
Formats the value using the given formatter.
§Errors
This function should return Err if, and only if, the provided Formatter returns Err.
String formatting is considered an infallible operation; this function only
returns a Result because writing to the underlying stream might fail and it must
provide a way to propagate the fact that an error has occurred back up the stack.
Implementors§
impl LowerHex for i8
impl LowerHex for i16
impl LowerHex for i32
impl LowerHex for i64
impl LowerHex for i128
impl LowerHex for isize
impl LowerHex for u8
impl LowerHex for u16
impl LowerHex for u32
impl LowerHex for u64
impl LowerHex for u128
impl LowerHex for usize
impl LowerHex for HexDisplay<'_>
impl LowerHex for bitcoin_hashes::hash160::Hash
impl LowerHex for bitcoin_hashes::ripemd160::Hash
impl LowerHex for bitcoin_hashes::sha1::Hash
impl LowerHex for bitcoin_hashes::sha256::Hash
impl LowerHex for Midstate
impl LowerHex for bitcoin_hashes::sha256d::Hash
impl LowerHex for bitcoin_hashes::sha512::Hash
impl LowerHex for bitcoin_hashes::sha512_256::Hash
impl LowerHex for bitcoin_hashes::siphash24::Hash
impl LowerHex for Bytes
impl LowerHex for BytesMut
impl LowerHex for Limb
impl LowerHex for ed25519::Signature
impl LowerHex for WithdrawReasons
impl LowerHex for Scalar
impl LowerHex for SecretKey
impl LowerHex for ValidationCodeHash
impl LowerHex for ExecutorParamsHash
impl LowerHex for ExecutorParamsPrepHash
impl LowerHex for H128
impl LowerHex for H160
impl LowerHex for H256
impl LowerHex for H384
impl LowerHex for H512
impl LowerHex for H768
impl LowerHex for U128
impl LowerHex for U256
impl LowerHex for U512
impl LowerHex for ElligatorSwift
impl LowerHex for PublicKey
impl LowerHex for XOnlyPublicKey
impl LowerHex for secp256k1::schnorr::Signature
impl LowerHex for Message
impl LowerHex for Capabilities
impl<'a> LowerHex for DisplayByteSlice<'a>
impl<'a, I> LowerHex for Format<'a, I>
impl<'a, T, O> LowerHex for Domain<'a, Const, T, O>
impl<'s, T> LowerHex for SliceVec<'s, T>where
T: LowerHex,
impl<A> LowerHex for TinyVec<A>
impl<A> LowerHex for ArrayVec<A>
impl<A, B> LowerHex for DisplayArray<A, B>
impl<A, O> LowerHex for BitArray<A, O>where
O: BitOrder,
A: BitViewSized,
impl<C> LowerHex for ecdsa::Signature<C>
impl<C> LowerHex for NonZeroScalar<C>where
C: CurveArithmetic,
impl<C> LowerHex for ScalarPrimitive<C>where
C: Curve,
impl<Size> LowerHex for EncodedPoint<Size>where
Size: ModulusSize,
impl<T> LowerHex for &T
impl<T> LowerHex for &mut T
impl<T> LowerHex for core::num::nonzero::NonZero<T>where
T: ZeroablePrimitive + LowerHex,
impl<T> LowerHex for Saturating<T>where
T: LowerHex,
impl<T> LowerHex for core::num::wrapping::Wrapping<T>where
T: LowerHex,
impl<T> LowerHex for Hmac<T>where
T: Hash,
impl<T> LowerHex for bitcoin_hashes::sha256t::Hash<T>where
T: Tag,
impl<T> LowerHex for crypto_bigint::non_zero::NonZero<T>
impl<T> LowerHex for crypto_bigint::wrapping::Wrapping<T>where
T: LowerHex,
impl<T> LowerHex for BitFlags<T>
impl<T> LowerHex for GenericArray<u8, T>
impl<T> LowerHex for FmtBinary<T>
tarpaulin_include only.impl<T> LowerHex for FmtDisplay<T>
tarpaulin_include only.impl<T> LowerHex for FmtList<T>
impl<T> LowerHex for FmtLowerExp<T>
tarpaulin_include only.impl<T> LowerHex for FmtLowerHex<T>where
T: LowerHex,
tarpaulin_include only.impl<T> LowerHex for FmtOctal<T>
tarpaulin_include only.impl<T> LowerHex for FmtPointer<T>
tarpaulin_include only.impl<T> LowerHex for FmtUpperExp<T>
tarpaulin_include only.impl<T> LowerHex for FmtUpperHex<T>
tarpaulin_include only.impl<T, O> LowerHex for BitBox<T, O>
impl<T, O> LowerHex for BitSlice<T, O>
§Bit-Slice Rendering
This implementation prints the contents of a &BitSlice in one of binary,
octal, or hexadecimal. It is important to note that this does not render the
raw underlying memory! They render the semantically-ordered contents of the
bit-slice as numerals. This distinction matters if you use type parameters that
differ from those presumed by your debugger (which is usually <u8, Msb0>).
The output separates the T elements as individual list items, and renders each
element as a base- 2, 8, or 16 numeric string. When walking an element, the bits
traversed by the bit-slice are considered to be stored in
most-significant-bit-first ordering. This means that index [0] is the high bit
of the left-most digit, and index [n] is the low bit of the right-most digit,
in a given printed word.
In order to render according to expectations of the Arabic numeral system, an
element being transcribed is chunked into digits from the least-significant end
of its rendered form. This is most noticeable in octal, which will always have a
smaller ceiling on the left-most digit in a printed word, while the right-most
digit in that word is able to use the full 0 ..= 7 numeral range.
§Examples
use bitvec::prelude::*;
let data = [
0b000000_10u8,
// digits print LTR
0b10_001_101,
// significance is computed RTL
0b01_000000,
];
let bits = &data.view_bits::<Msb0>()[6 .. 18];
assert_eq!(format!("{:b}", bits), "[10, 10001101, 01]");
assert_eq!(format!("{:o}", bits), "[2, 215, 1]");
assert_eq!(format!("{:X}", bits), "[2, 8D, 1]");The {:#} format modifier causes the standard 0b, 0o, or 0x prefix to be
applied to each printed word. The other format specifiers are not interpreted by
this implementation, and apply to the entire rendered text, not to individual
words.