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

    #[must_use]
    pub struct DebugList<'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 list of items as a part of your `Debug::fmt` implementation.

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

# Example

    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]

#### `fn entry(&mut self, entry: &Debug) -> &mut DebugList<'a, 'b>`

Adds a new entry to the list output.

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

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

#### `fn finish(&mut self) -> Result<(), Error>`

Finishes output and returns any error encountered.

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