Struct DebugTuple

pub struct DebugTuple<'a, 'b: 'a> { /* private fields */ }

A struct to help with 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 debug2::{pprint, Debug, Formatter};
use std::fmt;

struct Foo(i32, String);

impl Debug for Foo {
    fn fmt(&self, fmt: &mut Formatter) -> fmt::Result {
        fmt.debug_tuple("Foo")
            .field(&self.0)
            .field(&self.1)
            .finish()
    }
}

assert_eq!(
    pprint(Foo(10, "Hello World".to_string())),
    "Foo(10, \"Hello World\")",
);

Implementations

impl<'a, 'b: 'a> DebugTuple<'a, 'b>

pub fn field(&mut self, value: &dyn Debug) -> &mut Self

Adds a new field to the generated tuple struct output.

Examples

use debug2::{pprint, Debug, Formatter};
use std::fmt;

struct Foo(i32, String);

impl Debug for Foo {
    fn fmt(&self, fmt: &mut 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!(
    pprint(Foo(10, "Hello World".to_string())),
    "Foo(10, \"Hello World\")",
);

pub fn finish(&mut self) -> Result

Finishes output and returns any error encountered.

Examples

use debug2::{pprint, Debug, Formatter};
use std::fmt;

struct Foo(i32, String);

impl Debug for Foo {
    fn fmt(&self, fmt: &mut 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!(
    pprint(Foo(10, "Hello World".to_string())),
    "Foo(10, \"Hello World\")",
);