Trait ockam_core::compat::fmt::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§

1.0.0 · 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, }));

Trait ockam_core::compat::fmt::DisplayCopy item path

§Internationalization

§Examples

Required Methods§

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

§Examples

Implementors§

impl Display for Method

impl Display for Status

impl Display for RouteError

impl Display for ockam_core::compat::io::ErrorKind

impl Display for IpAddr

impl Display for SocketAddr

impl Display for BernoulliError

impl Display for WeightedError

impl Display for AsciiChar

impl Display for Infallible

impl Display for VarError

impl Display for std::sync::mpsc::RecvTimeoutError

impl Display for std::sync::mpsc::TryRecvError

impl Display for crossbeam_channel::err::RecvTimeoutError

impl Display for crossbeam_channel::err::TryRecvError

impl Display for FromHexError

impl Display for log::Level

impl Display for log::LevelFilter

impl Display for MietteError

impl Display for Type

impl Display for Array

impl Display for opentelemetry::common::Value

impl Display for opentelemetry::global::error_handler::Error

impl Display for LogError

impl Display for MetricsError

impl Display for TraceError

impl Display for Aggregation

impl Display for opentelemetry_sdk::runtime::TrySendError

impl Display for regex_syntax::ast::Ast

impl Display for regex_syntax::ast::Ast

impl Display for regex_syntax::ast::ErrorKind

impl Display for regex_syntax::ast::ErrorKind

impl Display for regex_syntax::error::Error

impl Display for regex_syntax::error::Error

impl Display for regex_syntax::hir::ErrorKind

impl Display for regex_syntax::hir::ErrorKind

impl Display for regex::error::Error

impl Display for serde_json::value::Value

impl Display for CollectionAllocErr

impl Display for strum::ParseError

impl Display for bool

impl Display for char

impl Display for f32

impl Display for f64

impl Display for i8

impl Display for i16

impl Display for i32

impl Display for i64

impl Display for i128

impl Display for isize

impl Display for !

impl Display for str

impl Display for u8

impl Display for u16

impl Display for u32

impl Display for u64

impl Display for u128

impl Display for usize

impl Display for ockam_core::api::Error

impl Display for Id

impl Display for ErrorCode

impl Display for FlowControlId

impl Display for Address

impl Display for AddressParseError

impl Display for Any

impl Display for ockam_core::Error

impl Display for OpenTelemetryContext

impl Display for ProtocolId

impl Display for Route

impl Display for TransportMessage

impl Display for TransportType

impl Display for ockam_core::compat::io::Error

impl Display for WriterPanicked

Trait ockam_core::compat::fmt::Display