Trait frame_support::dispatch::fmt::Binary

pub trait Binary {
    // Required method
    fn fmt(&self, f: &mut Formatter<'_>) -> Result<(), Error>;
}

b formatting.

The Binary trait should format its output as a number in binary.

For primitive signed integers (i8 to i128, and isize), negative values are formatted as the two’s complement representation.

The alternate flag, #, adds a 0b in front of the output.

For more information on formatters, see the module-level documentation.

Examples

Basic usage with i32:

let x = 42; // 42 is '101010' in binary

assert_eq!(format!("{x:b}"), "101010");
assert_eq!(format!("{x:#b}"), "0b101010");

assert_eq!(format!("{:b}", -16), "11111111111111111111111111110000");

Implementing Binary on a type:

use std::fmt;

struct Length(i32);

impl fmt::Binary for Length {
    fn fmt(&self, f: &mut fmt::Formatter<'_>) -> fmt::Result {
        let val = self.0;

        fmt::Binary::fmt(&val, f) // delegate to i32's implementation
    }
}

let l = Length(107);

assert_eq!(format!("l as binary is: {l:b}"), "l as binary is: 1101011");

assert_eq!(
    // Note that the `0b` prefix added by `#` is included in the total width, so we
    // need to add two to correctly display all 32 bits.
    format!("l as binary is: {l:#034b}"),
    "l as binary is: 0b00000000000000000000000001101011"
);

Required Methods

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 Binary for i8

impl Binary for i16

impl Binary for i32

impl Binary for i64

impl Binary for i128

impl Binary for isize

impl Binary for u8

impl Binary for u16

impl Binary for u32

impl Binary for u64

impl Binary for u128

impl Binary for usize

impl Binary for FrameFlags

impl Binary for CreateFlags

impl Binary for ReadFlags

impl Binary for WatchFlags

impl Binary for Access

impl Binary for AtFlags

impl Binary for FallocateFlags

impl Binary for MemfdFlags

impl Binary for Mode

impl Binary for OFlags

impl Binary for RenameFlags

impl Binary for ResolveFlags

impl Binary for SealFlags

impl Binary for StatVfsMountFlags

impl Binary for StatxFlags

impl Binary for DupFlags

impl Binary for FdFlags

impl Binary for ReadWriteFlags

impl Binary for MapFlags

impl Binary for MlockAllFlags

impl Binary for MlockFlags

impl Binary for MprotectFlags

impl Binary for MremapFlags

impl Binary for MsyncFlags

impl Binary for ProtFlags

impl Binary for UserfaultfdFlags

impl Binary for MountFlags

impl Binary for MountPropagationFlags

impl Binary for UnmountFlags

impl Binary for Flags

impl Binary for TimerfdFlags

impl Binary for TimerfdTimerFlags

impl Binary for IFlags

impl Binary for XattrFlags

impl Binary for MembarrierQuery

impl Binary for PidfdFlags

impl Binary for PidfdGetfdFlags

impl Binary for FloatingPointEmulationControl

impl Binary for FloatingPointExceptionMode

impl Binary for SpeculationFeatureControl

impl Binary for SpeculationFeatureState

impl Binary for UnalignedAccessControl

impl Binary for WaitOptions

impl Binary for WaitidOptions

impl Binary for CapabilityFlags

impl Binary for CapabilitiesSecureBits

impl Binary for TaggedAddressMode

impl Binary for ThreadNameSpaceType

impl Binary for UnshareFlags

impl Binary for Capabilities

impl Binary for WithdrawReasons

impl Binary for FilterId

impl<'a, I> Binary for Format<'a, I>

where I: Iterator, <I as Iterator>::Item: Binary,

impl<'a, T> Binary for StyledValue<'a, T>

where T: Binary,

impl<'a, T, O> Binary for Domain<'a, Const, T, O>

where O: BitOrder, T: BitStore,

impl<'s, T> Binary for SliceVec<'s, T>

where T: Binary,

impl<A> Binary for TinyVec<A>

where A: Array, <A as Array>::Item: Binary,

impl<A> Binary for ArrayVec<A>

where A: Array, <A as Array>::Item: Binary,

impl<A, O> Binary for BitArray<A, O>

where O: BitOrder, A: BitViewSized,

impl<O> Binary for I16<O>

where O: ByteOrder,

impl<O> Binary for I32<O>

where O: ByteOrder,

impl<O> Binary for I64<O>

where O: ByteOrder,

impl<O> Binary for I128<O>

where O: ByteOrder,

impl<O> Binary for U16<O>

where O: ByteOrder,

impl<O> Binary for U32<O>

where O: ByteOrder,

impl<O> Binary for U64<O>

where O: ByteOrder,

impl<O> Binary for U128<O>

where O: ByteOrder,

impl<R> Binary for BitEnd<R>

where R: BitRegister,

impl<R> Binary for BitIdx<R>

where R: BitRegister,

impl<R> Binary for BitMask<R>

where R: BitRegister,

impl<R> Binary for BitPos<R>

where R: BitRegister,

impl<R> Binary for BitSel<R>

where R: BitRegister,

impl<T> Binary for &T

where T: Binary + ?Sized,

impl<T> Binary for &mut T

where T: Binary + ?Sized,

impl<T> Binary for FmtBinary<T>

where T: Binary,

impl<T> Binary for FmtDisplay<T>

where T: Display + Binary,

impl<T> Binary for FmtList<T>

where &'a T: for<'a> IntoIterator, <&'a T as IntoIterator>::Item: for<'a> Binary,

impl<T> Binary for FmtLowerExp<T>

where T: LowerExp + Binary,

impl<T> Binary for FmtLowerHex<T>

where T: LowerHex + Binary,

impl<T> Binary for FmtOctal<T>

where T: Octal + Binary,

impl<T> Binary for FmtPointer<T>

where T: Pointer + Binary,

impl<T> Binary for FmtUpperExp<T>

where T: UpperExp + Binary,

impl<T> Binary for FmtUpperHex<T>

where T: UpperHex + Binary,

impl<T> Binary for NonZero<T>

where T: ZeroablePrimitive + Binary,

impl<T> Binary for Saturating<T>

where T: Binary,

impl<T> Binary for Wrapping<T>

where T: Binary,

impl<T, O> Binary for BitSlice<T, O>

where T: BitStore, O: BitOrder,

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.