Struct std::fmt::DebugTuple
pub struct DebugTuple<'a, 'b> where 'b: 'a, { /* fields omitted */ }
A struct to help with fmt::Debug implementations.
This is useful when you wish to output a formatted tuple as a part of your Debug::fmt implementation.
This can be constructed by the Formatter::debug_tuple method.
Examples
use std::fmt;
struct Foo(i32, String);
impl fmt::Debug for Foo {
fn fmt(&self, fmt: &mut fmt::Formatter) -> fmt::Result {
fmt.debug_tuple("Foo")
.field(&self.0)
.field(&self.1)
.finish()
}
}
assert_eq!(
format!("{:?}", Foo(10, "Hello World".to_string())),
"Foo(10, \"Hello World\")",
);Implementations
impl<'a, 'b> DebugTuple<'a, 'b> where
'b: 'a,
pub fn field(&mut self, value: &dyn Debug) -> &mut DebugTuple<'a, 'b>
Adds a new field to the generated tuple struct output.
Examples
use std::fmt;
struct Foo(i32, String);
impl fmt::Debug for Foo {
fn fmt(&self, fmt: &mut fmt::Formatter<'_>) -> fmt::Result {
fmt.debug_tuple("Foo")
.field(&self.0) // We add the first field.
.field(&self.1) // We add the second field.
.finish() // We're good to go!
}
}
assert_eq!(
format!("{:?}", Foo(10, "Hello World".to_string())),
"Foo(10, \"Hello World\")",
);pub fn finish(&mut self) -> Result<(), Error>
Finishes output and returns any error encountered.
Examples
use std::fmt;
struct Foo(i32, String);
impl fmt::Debug for Foo {
fn fmt(&self, fmt: &mut fmt::Formatter<'_>) -> fmt::Result {
fmt.debug_tuple("Foo")
.field(&self.0)
.field(&self.1)
.finish() // You need to call it to "finish" the
// tuple formatting.
}
}
assert_eq!(
format!("{:?}", Foo(10, "Hello World".to_string())),
"Foo(10, \"Hello World\")",
);Auto Trait Implementations
impl<'a, 'b> !RefUnwindSafe for DebugTuple<'a, 'b>
impl<'a, 'b> !Send for DebugTuple<'a, 'b>
impl<'a, 'b> !Sync for DebugTuple<'a, 'b>
impl<'a, 'b> Unpin for DebugTuple<'a, 'b> where
'b: 'a,
impl<'a, 'b> !UnwindSafe for DebugTuple<'a, 'b>
Blanket Implementations
impl<T> From<T> for T
pub fn from(t: T) -> T
Performs the conversion.
pub fn into(self) -> U
Performs the conversion.
type Error = Infallible
The type returned in the event of a conversion error.
pub fn try_from(value: U) -> Result<T, <T as TryFrom<U>>::Error>
Performs the conversion.
type Error = <U as TryFrom<T>>::Error
The type returned in the event of a conversion error.
pub fn try_into(self) -> Result<U, <U as TryFrom<T>>::Error>
Performs the conversion.
© 2010 The Rust Project Developers
Licensed under the Apache License, Version 2.0 or the MIT license, at your option.
https://doc.rust-lang.org/std/fmt/struct.DebugTuple.html