# 1.2.0[−][src]Struct alloc::fmt::DebugList

    #[must_use = "must eventually call `finish()` on Debug builders"]
    pub struct DebugList<'a, 'b> where
        'b: 'a,
        'b: 'a,
        'b: 'b,  { /* fields omitted */ }

A struct to help with `fmt::Debug` implementations.

This is useful when you wish to output a formatted list of items as a part of your `Debug::fmt` implementation.

This can be constructed by the `Formatter::debug_list` method.

# Examples

    use std::fmt;

    struct Foo(Vec<i32>);

    impl fmt::Debug for Foo {
        fn fmt(&self, fmt: &mut fmt::Formatter) -> fmt::Result {
            fmt.debug_list().entries(self.0.iter()).finish()
        }
    }

    // prints "[10, 11]"
    println!("{:?}", Foo(vec![10, 11]));

## Methods

###

`impl<'a, 'b> DebugList<'a, 'b> where 'b: 'a,` | [src]

####

`pub fn entry(&mut self, entry: &dyn Debug) -> &mut DebugList<'a, 'b>` | [src]

Adds a new entry to the list output.

####

`pub fn entries<D, I>(&mut self, entries: I) -> &mut DebugList<'a, 'b> where D: Debug, I: IntoIterator<Item = D>,` | [src]

Adds the contents of an iterator of entries to the list output.

####

`pub fn finish(&mut self) -> Result<(), Error>` | [src]

Finishes output and returns any error encountered.

## Auto Trait Implementations

###

`impl<'a, 'b> !Send for DebugList<'a, 'b>` |

###

`impl<'a, 'b> !Sync for DebugList<'a, 'b>` |

## Blanket Implementations

###

`impl<T> From for T` | [src]

####

`fn from(t: T) -> T` | [src]

Performs the conversion.

###

`impl<T, U> TryFrom for T where T: From<U>,` | [src]

#### `type Error = !`

🔬 This is a nightly-only experimental API. (`try_from` #33417)

The type returned in the event of a conversion error.

####

`fn try_from(value: U) -> Result<T, <T as TryFrom<U>>::Error>` | [src]

🔬 This is a nightly-only experimental API. (`try_from` #33417)

Performs the conversion.

###

`impl<T, U> TryInto for T where U: TryFrom<T>,` | [src]

#### `type Error = <U as TryFrom<T>>::Error`

🔬 This is a nightly-only experimental API. (`try_from` #33417)

The type returned in the event of a conversion error.

####

`fn try_into(self) -> Result<U, <U as TryFrom<T>>::Error>` | [src]

🔬 This is a nightly-only experimental API. (`try_from` #33417)

Performs the conversion.

###

`impl<T, U> Into for T where U: From<T>,` | [src]

####

`fn into(self) -> U` | [src]

Performs the conversion.

###

`impl<T> Borrow for T where T: ?Sized,` | [src]

####

`fn borrow(&self) -> &T` | [src]

Immutably borrows from an owned value. Read more

###

`impl<T> BorrowMut for T where T: ?Sized,` | [src]

####

`fn borrow_mut(&mut self) -> &mut T` | [src]

Mutably borrows from an owned value. Read more

###

`impl<T> Any for T where T: 'static + ?Sized,` | [src]

####

`fn get_type_id(&self) -> TypeId` | [src]

🔬 This is a nightly-only experimental API. (`get_type_id` #27745)

this method will likely be replaced by an associated static

Gets the `TypeId` of `self`. Read more

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