Trait serde::lib::Display

1.0.0 · source ·
pub trait Display {
    // Required method
    fn fmt(&self, f: &mut Formatter<'_>) -> Result<(), Error>;
}
Expand description

Format trait for an empty format, {}.

Implementing this trait for a type will automatically implement the ToString trait for the type, allowing the usage of the .to_string() method. Prefer implementing the Display trait for a type, rather than ToString.

Display is similar to Debug, but Display is for user-facing output, and so cannot be derived.

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

§Internationalization

Because a type can only have one Display implementation, it is often preferable to only implement Display when there is a single most “obvious” way that values can be formatted as text. This could mean formatting according to the “invariant” culture and “undefined” locale, or it could mean that the type display is designed for a specific culture/locale, such as developer logs.

If not all values have a justifiably canonical textual format or if you want to support alternative formats not covered by the standard set of possible formatting traits, the most flexible approach is display adapters: methods like str::escape_default or Path::display which create a wrapper implementing Display to output the specific display format.

§Examples

Implementing Display on a type:

use std::fmt;

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

impl fmt::Display for Point {
    fn fmt(&self, f: &mut fmt::Formatter<'_>) -> fmt::Result {
        write!(f, "({}, {})", self.x, self.y)
    }
}

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

assert_eq!(format!("The origin is: {origin}"), "The origin is: (0, 0)");

Required Methods§

source

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

Formats the value using the given formatter.

§Examples
use std::fmt;

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

impl fmt::Display for Position {
    fn fmt(&self, f: &mut fmt::Formatter<'_>) -> fmt::Result {
        write!(f, "({}, {})", self.longitude, self.latitude)
    }
}

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

Implementors§

1.34.0 · source§

impl Display for Infallible

source§

impl Display for AsciiChar

source§

impl Display for VarError

1.60.0 · source§

impl Display for ErrorKind

1.15.0 · source§

impl Display for RecvTimeoutError

source§

impl Display for TryRecvError

1.7.0 · source§

impl Display for IpAddr

source§

impl Display for SocketAddr

source§

impl Display for bool

source§

impl Display for char

source§

impl Display for f32

source§

impl Display for f64

source§

impl Display for i8

source§

impl Display for i16

source§

impl Display for i32

source§

impl Display for i64

source§

impl Display for i128

source§

impl Display for isize

source§

impl Display for !

source§

impl Display for str

source§

impl Display for u8

source§

impl Display for u16

source§

impl Display for u32

source§

impl Display for u64

source§

impl Display for u128

source§

impl Display for usize

source§

impl Display for OneOf

source§

impl Display for WithDecimalPoint

source§

impl Display for serde::de::value::Error

source§

impl Display for AllocError

1.28.0 · source§

impl Display for LayoutError

1.36.0 · source§

impl Display for TryFromSliceError

1.39.0 · source§

impl Display for serde::lib::core::ascii::EscapeDefault

1.65.0 · source§

impl Display for Backtrace

1.13.0 · source§

impl Display for BorrowError

1.13.0 · source§

impl Display for BorrowMutError

1.34.0 · source§

impl Display for CharTryFromError

1.9.0 · source§

impl Display for DecodeUtf16Error

1.20.0 · source§

impl Display for serde::lib::core::char::EscapeDebug

1.16.0 · source§

impl Display for serde::lib::core::char::EscapeDefault

1.16.0 · source§

impl Display for serde::lib::core::char::EscapeUnicode

1.20.0 · source§

impl Display for ParseCharError

1.16.0 · source§

impl Display for ToLowercase

1.16.0 · source§

impl Display for ToUppercase

1.59.0 · source§

impl Display for TryFromCharError

source§

impl Display for UnorderedKeyError

1.57.0 · source§

impl Display for TryReserveError

source§

impl Display for JoinPathsError

source§

impl Display for serde::lib::core::ffi::os_str::Display<'_>

1.69.0 · source§

impl Display for FromBytesUntilNulError

1.17.0 · source§

impl Display for FromBytesWithNulError

1.58.0 · source§

impl Display for FromVecWithNulError

1.7.0 · source§

impl Display for IntoStringError

source§

impl Display for NulError

source§

impl Display for serde::lib::core::io::Error

1.56.0 · source§

impl Display for WriterPanicked

1.26.0 · source§

impl Display for Location<'_>

1.26.0 · source§

impl Display for PanicInfo<'_>

source§

impl Display for serde::lib::core::path::Display<'_>

1.7.0 · source§

impl Display for StripPrefixError

source§

impl Display for ExitStatus

source§

impl Display for ExitStatusError

source§

impl Display for FromUtf8Error

source§

impl Display for FromUtf16Error

source§

impl Display for RecvError

1.26.0 · source§

impl Display for AccessError

1.8.0 · source§

impl Display for SystemTimeError

1.66.0 · source§

impl Display for TryFromFloatSecsError

source§

impl Display for Arguments<'_>

source§

impl Display for serde::lib::fmt::Error

1.4.0 · source§

impl Display for AddrParseError

source§

impl Display for Ipv4Addr

source§

impl Display for Ipv6Addr

Write an Ipv6Addr, conforming to the canonical style described by RFC 5952.

source§

impl Display for SocketAddrV4

source§

impl Display for SocketAddrV6

source§

impl Display for ParseFloatError

source§

impl Display for ParseIntError

1.34.0 · source§

impl Display for TryFromIntError

source§

impl Display for ParseBoolError

source§

impl Display for Utf8Error

source§

impl Display for String

source§

impl<'a> Display for Unexpected<'a>

1.60.0 · source§

impl<'a> Display for EscapeAscii<'a>

1.34.0 · source§

impl<'a> Display for serde::lib::str::EscapeDebug<'a>

1.34.0 · source§

impl<'a> Display for serde::lib::str::EscapeDefault<'a>

1.34.0 · source§

impl<'a> Display for serde::lib::str::EscapeUnicode<'a>

source§

impl<'a> Display for dyn Expected + 'a

source§

impl<'a, K, V> Display for serde::lib::core::collections::hash_map::OccupiedError<'a, K, V>
where K: Debug, V: Debug,

source§

impl<'a, K, V, A> Display for serde::lib::core::collections::btree_map::OccupiedError<'a, K, V, A>
where K: Debug + Ord, V: Debug, A: Allocator + Clone,

source§

impl<B> Display for Cow<'_, B>
where B: Display + ToOwned + ?Sized, <B as ToOwned>::Owned: Display,

source§

impl<E> Display for Report<E>
where E: Error,

source§

impl<F> Display for FormatterFn<F>
where F: Fn(&mut Formatter<'_>) -> Result<(), Error>,

1.33.0 · source§

impl<Ptr> Display for Pin<Ptr>
where Ptr: Display,

source§

impl<T> Display for TryLockError<T>

source§

impl<T> Display for TrySendError<T>

source§

impl<T> Display for &T
where T: Display + ?Sized,

source§

impl<T> Display for &mut T
where T: Display + ?Sized,

source§

impl<T> Display for ThinBox<T>
where T: Display + ?Sized,

1.20.0 · source§

impl<T> Display for Ref<'_, T>
where T: Display + ?Sized,

1.20.0 · source§

impl<T> Display for RefMut<'_, T>
where T: Display + ?Sized,

source§

impl<T> Display for SendError<T>

source§

impl<T> Display for MappedMutexGuard<'_, T>
where T: Display + ?Sized,

source§

impl<T> Display for MappedRwLockReadGuard<'_, T>
where T: Display + ?Sized,

source§

impl<T> Display for MappedRwLockWriteGuard<'_, T>
where T: Display + ?Sized,

1.20.0 · source§

impl<T> Display for MutexGuard<'_, T>
where T: Display + ?Sized,

source§

impl<T> Display for PoisonError<T>

source§

impl<T> Display for ReentrantLockGuard<'_, T>
where T: Display + ?Sized,

1.20.0 · source§

impl<T> Display for RwLockReadGuard<'_, T>
where T: Display + ?Sized,

1.20.0 · source§

impl<T> Display for RwLockWriteGuard<'_, T>
where T: Display + ?Sized,

1.28.0 · source§

impl<T> Display for NonZero<T>

1.74.0 · source§

impl<T> Display for Saturating<T>
where T: Display,

1.10.0 · source§

impl<T> Display for Wrapping<T>
where T: Display,

source§

impl<T, A> Display for Arc<T, A>
where T: Display + ?Sized, A: Allocator,

source§

impl<T, A> Display for Box<T, A>
where T: Display + ?Sized, A: Allocator,

source§

impl<T, A> Display for Rc<T, A>
where T: Display + ?Sized, A: Allocator,

source§

impl<W> Display for IntoInnerError<W>

source§

impl<const N: usize> Display for GetManyMutError<N>