Trait nom::lib::std::fmt::Debug1.0.0[−][src]

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

[−]

? formatting.

Debug should format the output in a programmer-facing, debugging context.

Generally speaking, you should just derive a Debug implementation.

When used with the alternate format specifier #?, the output is pretty-printed.

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

This trait can be used with #[derive] if all fields implement Debug. When derived for structs, it will use the name of the struct, then {, then a comma-separated list of each field’s name and Debug value, then }. For enums, it will use the name of the variant and, if applicable, (, then the Debug values of the fields, then ).

Stability

Derived Debug formats are not stable, and so may change with future Rust versions. Additionally, Debug implementations of types provided by the standard library (libstd, libcore, liballoc, etc.) are not stable, and may also change with future Rust versions.

Examples

Deriving an implementation:

#[derive(Debug)]
struct Point {
    x: i32,
    y: i32,
}

let origin = Point { x: 0, y: 0 };

assert_eq!(format!("The origin is: {:?}", origin), "The origin is: Point { x: 0, y: 0 }");

Manually implementing:

use std::fmt;

struct Point {
    x: i32,
    y: i32,
}

impl fmt::Debug for Point {
    fn fmt(&self, f: &mut fmt::Formatter<'_>) -> fmt::Result {
        f.debug_struct("Point")
         .field("x", &self.x)
         .field("y", &self.y)
         .finish()
    }
}

let origin = Point { x: 0, y: 0 };

assert_eq!(format!("The origin is: {:?}", origin), "The origin is: Point { x: 0, y: 0 }");

There are a number of helper methods on the Formatter struct to help you with manual implementations, such as debug_struct.

Debug implementations using either derive or the debug builder API on Formatter support pretty-printing using the alternate flag: {:#?}.

Pretty-printing with #?:

#[derive(Debug)]
struct Point {
    x: i32,
    y: i32,
}

let origin = Point { x: 0, y: 0 };

assert_eq!(format!("The origin is: {:#?}", origin),
"The origin is: Point {
    x: 0,
    y: 0,
}");

Required methods

`pub fn fmt(&self, f: &mut Formatter<'_>) -> Result<(), Error>`[src][−]

Formats the value using the given formatter.

Examples

use std::fmt;

struct Position {
    longitude: f32,
    latitude: f32,
}

impl fmt::Debug for Position {
    fn fmt(&self, f: &mut fmt::Formatter<'_>) -> fmt::Result {
        f.debug_tuple("")
         .field(&self.longitude)
         .field(&self.latitude)
         .finish()
    }
}

let position = Position { longitude: 1.987, latitude: 2.983 };
assert_eq!(format!("{:?}", position), "(1.987, 2.983)");

assert_eq!(format!("{:#?}", position), "(
    1.987,
    2.983,
)");

Trait nom::lib::std::fmt::Debug⎘1.0.0[−][src]

Stability

Examples

Required methods

pub fn fmt(&self, f: &mut Formatter<'_>) -> Result<(), Error>[src][−]

Examples

Implementations on Foreign Types

impl Debug for EscapeUnicode[src][−]

pub fn fmt(&self, f: &mut Formatter<'_>) -> Result<(), Error>[src]

impl<'a> Debug for Location<'a>[src][−]

pub fn fmt(&self, f: &mut Formatter<'_>) -> Result<(), Error>[src]

impl Debug for TryFromSliceError[src][−]

pub fn fmt(&self, f: &mut Formatter<'_>) -> Result<(), Error>[src]

impl Debug for __m128bh[src][−]

pub fn fmt(&self, f: &mut Formatter<'_>) -> Result<(), Error>[src]

impl Debug for __m128d[src][−]

pub fn fmt(&self, f: &mut Formatter<'_>) -> Result<(), Error>[src]

impl Debug for AtomicU16[src][−]

pub fn fmt(&self, f: &mut Formatter<'_>) -> Result<(), Error>[src]

impl<'_, T> Debug for RefMut<'_, T> where T: Debug + ?Sized, [src][−]

pub fn fmt(&self, f: &mut Formatter<'_>) -> Result<(), Error>[src]

impl Debug for __m512[src][−]

pub fn fmt(&self, f: &mut Formatter<'_>) -> Result<(), Error>[src]

impl Debug for AtomicIsize[src][−]

pub fn fmt(&self, f: &mut Formatter<'_>) -> Result<(), Error>[src]

impl Debug for AtomicI16[src][−]

pub fn fmt(&self, f: &mut Formatter<'_>) -> Result<(), Error>[src]

impl Debug for SipHasher[src][−]

pub fn fmt(&self, f: &mut Formatter<'_>) -> Result<(), Error>[src]

impl Debug for NonZeroI128[src][−]

pub fn fmt(&self, f: &mut Formatter<'_>) -> Result<(), Error>[src]

impl Debug for Duration[src][−]

pub fn fmt(&self, f: &mut Formatter<'_>) -> Result<(), Error>[src]

impl Debug for __m512d[src][−]

pub fn fmt(&self, f: &mut Formatter<'_>) -> Result<(), Error>[src]

impl<T> Debug for Cell<T> where T: Copy + Debug, [src][−]

pub fn fmt(&self, f: &mut Formatter<'_>) -> Result<(), Error>[src]

impl Debug for LayoutError[src][−]

pub fn fmt(&self, f: &mut Formatter<'_>) -> Result<(), Error>[src]

impl Debug for __m128i[src][−]

pub fn fmt(&self, f: &mut Formatter<'_>) -> Result<(), Error>[src]

impl Debug for ToLowercase[src][−]

pub fn fmt(&self, f: &mut Formatter<'_>) -> Result<(), Error>[src]

impl Debug for PhantomPinned[src][−]

pub fn fmt(&self, f: &mut Formatter<'_>) -> Result<(), Error>[src]

impl Debug for __m256bh[src][−]

pub fn fmt(&self, f: &mut Formatter<'_>) -> Result<(), Error>[src]

impl Debug for AtomicU32[src][−]

pub fn fmt(&self, f: &mut Formatter<'_>) -> Result<(), Error>[src]

impl<I> Debug for DecodeUtf16<I> where I: Debug + Iterator<Item = u16>, [src][−]

pub fn fmt(&self, f: &mut Formatter<'_>) -> Result<(), Error>[src]

impl Debug for AtomicI32[src][−]

pub fn fmt(&self, f: &mut Formatter<'_>) -> Result<(), Error>[src]

impl Debug for AtomicBool[src][−]

pub fn fmt(&self, f: &mut Formatter<'_>) -> Result<(), Error>[src]

impl<'_> Debug for Context<'_>[src][−]

pub fn fmt(&self, f: &mut Formatter<'_>) -> Result<(), Error>[src]

impl Debug for CpuidResult[src][−]

pub fn fmt(&self, f: &mut Formatter<'_>) -> Result<(), Error>[src]

impl Debug for NonZeroIsize[src][−]

pub fn fmt(&self, f: &mut Formatter<'_>) -> Result<(), Error>[src]

impl Debug for NonZeroU128[src][−]

pub fn fmt(&self, f: &mut Formatter<'_>) -> Result<(), Error>[src]

impl Debug for NonZeroI64[src][−]

pub fn fmt(&self, f: &mut Formatter<'_>) -> Result<(), Error>[src]

impl<T> Debug for PhantomData<T> where T: ?Sized, [src][−]

pub fn fmt(&self, f: &mut Formatter<'_>) -> Result<(), Error>[src]

impl Debug for AtomicUsize[src][−]

pub fn fmt(&self, f: &mut Formatter<'_>) -> Result<(), Error>[src]

impl<T> Debug for RefCell<T> where T: Debug + ?Sized, [src][−]

pub fn fmt(&self, f: &mut Formatter<'_>) -> Result<(), Error>[src]

impl Debug for BorrowMutError[src][−]

pub fn fmt(&self, f: &mut Formatter<'_>) -> Result<(), Error>[src]

impl Debug for NonZeroI32[src][−]

pub fn fmt(&self, f: &mut Formatter<'_>) -> Result<(), Error>[src]

impl Debug for NonZeroI16[src][−]

pub fn fmt(&self, f: &mut Formatter<'_>) -> Result<(), Error>[src]

impl Debug for RawWaker[src][−]

pub fn fmt(&self, f: &mut Formatter<'_>) -> Result<(), Error>[src]

impl Debug for ParseIntError[src][−]

Trait nom::lib::std::fmt::Debug1.0.0[−][src]

`pub fn fmt(&self, f: &mut Formatter<'_>) -> Result<(), Error>`[src][−]

`impl Debug for EscapeUnicode`[src][−]

`pub fn fmt(&self, f: &mut Formatter<'_>) -> Result<(), Error>`[src]

`impl<'a> Debug for Location<'a>`[src][−]

`pub fn fmt(&self, f: &mut Formatter<'_>) -> Result<(), Error>`[src]

`impl Debug for TryFromSliceError`[src][−]

`pub fn fmt(&self, f: &mut Formatter<'_>) -> Result<(), Error>`[src]

`impl Debug for __m128bh`[src][−]

`pub fn fmt(&self, f: &mut Formatter<'_>) -> Result<(), Error>`[src]

`impl Debug for __m128d`[src][−]

`pub fn fmt(&self, f: &mut Formatter<'_>) -> Result<(), Error>`[src]

`impl Debug for AtomicU16`[src][−]

`pub fn fmt(&self, f: &mut Formatter<'_>) -> Result<(), Error>`[src]

`impl<'_, T> Debug for RefMut<'_, T> where T: Debug + ?Sized,` [src][−]

`pub fn fmt(&self, f: &mut Formatter<'_>) -> Result<(), Error>`[src]

`impl Debug for __m512`[src][−]

`pub fn fmt(&self, f: &mut Formatter<'_>) -> Result<(), Error>`[src]

`impl Debug for AtomicIsize`[src][−]

`pub fn fmt(&self, f: &mut Formatter<'_>) -> Result<(), Error>`[src]

`impl Debug for AtomicI16`[src][−]

`pub fn fmt(&self, f: &mut Formatter<'_>) -> Result<(), Error>`[src]

`impl Debug for SipHasher`[src][−]

`pub fn fmt(&self, f: &mut Formatter<'_>) -> Result<(), Error>`[src]

`impl Debug for NonZeroI128`[src][−]

`pub fn fmt(&self, f: &mut Formatter<'_>) -> Result<(), Error>`[src]

`impl Debug for Duration`[src][−]

`pub fn fmt(&self, f: &mut Formatter<'_>) -> Result<(), Error>`[src]

`impl Debug for __m512d`[src][−]

`pub fn fmt(&self, f: &mut Formatter<'_>) -> Result<(), Error>`[src]

`impl<T> Debug for Cell<T> where T: Copy + Debug,` [src][−]

`pub fn fmt(&self, f: &mut Formatter<'_>) -> Result<(), Error>`[src]

`impl Debug for LayoutError`[src][−]

`pub fn fmt(&self, f: &mut Formatter<'_>) -> Result<(), Error>`[src]

`impl Debug for __m128i`[src][−]

`pub fn fmt(&self, f: &mut Formatter<'_>) -> Result<(), Error>`[src]

`impl Debug for ToLowercase`[src][−]

`pub fn fmt(&self, f: &mut Formatter<'_>) -> Result<(), Error>`[src]

`impl Debug for PhantomPinned`[src][−]

`pub fn fmt(&self, f: &mut Formatter<'_>) -> Result<(), Error>`[src]

`impl Debug for __m256bh`[src][−]

`pub fn fmt(&self, f: &mut Formatter<'_>) -> Result<(), Error>`[src]

`impl Debug for AtomicU32`[src][−]

`pub fn fmt(&self, f: &mut Formatter<'_>) -> Result<(), Error>`[src]

`impl<I> Debug for DecodeUtf16<I> where I: Debug + Iterator<Item = u16>,` [src][−]

`pub fn fmt(&self, f: &mut Formatter<'_>) -> Result<(), Error>`[src]

`impl Debug for AtomicI32`[src][−]

`pub fn fmt(&self, f: &mut Formatter<'_>) -> Result<(), Error>`[src]

`impl Debug for AtomicBool`[src][−]

`pub fn fmt(&self, f: &mut Formatter<'_>) -> Result<(), Error>`[src]

`impl<'_> Debug for Context<'_>`[src][−]

`pub fn fmt(&self, f: &mut Formatter<'_>) -> Result<(), Error>`[src]

`impl Debug for CpuidResult`[src][−]

`pub fn fmt(&self, f: &mut Formatter<'_>) -> Result<(), Error>`[src]

`impl Debug for NonZeroIsize`[src][−]

`pub fn fmt(&self, f: &mut Formatter<'_>) -> Result<(), Error>`[src]

`impl Debug for NonZeroU128`[src][−]

`pub fn fmt(&self, f: &mut Formatter<'_>) -> Result<(), Error>`[src]

`impl Debug for NonZeroI64`[src][−]

`pub fn fmt(&self, f: &mut Formatter<'_>) -> Result<(), Error>`[src]

`impl<T> Debug for PhantomData<T> where T: ?Sized,` [src][−]

`pub fn fmt(&self, f: &mut Formatter<'_>) -> Result<(), Error>`[src]

`impl Debug for AtomicUsize`[src][−]

`pub fn fmt(&self, f: &mut Formatter<'_>) -> Result<(), Error>`[src]

`impl<T> Debug for RefCell<T> where T: Debug + ?Sized,` [src][−]

`pub fn fmt(&self, f: &mut Formatter<'_>) -> Result<(), Error>`[src]

`impl Debug for BorrowMutError`[src][−]

`pub fn fmt(&self, f: &mut Formatter<'_>) -> Result<(), Error>`[src]

`impl Debug for NonZeroI32`[src][−]

`pub fn fmt(&self, f: &mut Formatter<'_>) -> Result<(), Error>`[src]

`impl Debug for NonZeroI16`[src][−]

`pub fn fmt(&self, f: &mut Formatter<'_>) -> Result<(), Error>`[src]

`impl Debug for RawWaker`[src][−]

`pub fn fmt(&self, f: &mut Formatter<'_>) -> Result<(), Error>`[src]

`impl Debug for ParseIntError`[src][−]

`pub fn fmt(&self, f: &mut Formatter<'_>) -> Result<(), Error>`[src]

`impl Debug for Layout`[src][−]

`pub fn fmt(&self, f: &mut Formatter<'_>) -> Result<(), Error>`[src]

`impl<T> Debug for OnceCell<T> where T: Debug,` [src][−]

`pub fn fmt(&self, f: &mut Formatter<'_>) -> Result<(), Error>`[src]