# Struct alloc::fmt::FormatterFn

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    pub struct FormatterFn<F>(pub F)
    where
        F: Fn(&mut Formatter<'_>) -> Result<(), Error>;

🔬This is a nightly-only experimental API. (`debug_closure_helpers` #117729)
Expand description

Implements `fmt::Debug` and `fmt::Display` using a function.

## §Examples

    #![feature(debug_closure_helpers)]
    use std::fmt;

    let value = 'a';
    assert_eq!(format!("{}", value), "a");
    assert_eq!(format!("{:?}", value), "'a'");

    let wrapped = fmt::FormatterFn(|f| write!(f, "{:?}", &value));
    assert_eq!(format!("{}", wrapped), "'a'");
    assert_eq!(format!("{:?}", wrapped), "'a'");

Run

## Tuple Fields§

§`0: F`
🔬This is a nightly-only experimental API. (`debug_closure_helpers` #117729)

## Trait Implementations§

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### impl<F> Debug for FormatterFn<F>
where F: Fn(&mut Formatter<'_>) -> Result<(), Error>,

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

Formats the value using the given formatter. Read more
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### impl<F> Display for FormatterFn<F>
where F: Fn(&mut Formatter<'_>) -> Result<(), Error>,

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

Formats the value using the given formatter. Read more

## Auto Trait Implementations§

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### impl<F> RefUnwindSafe for FormatterFn<F>
where F: RefUnwindSafe,

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### impl<F> Send for FormatterFn<F>
where F: Send,

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### impl<F> Sync for FormatterFn<F>
where F: Sync,

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### impl<F> Unpin for FormatterFn<F>
where F: Unpin,

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### impl<F> UnwindSafe for FormatterFn<F>
where F: UnwindSafe,

## Blanket Implementations§

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### impl<T> Any for T
where T: 'static + ?Sized,

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#### fn type_id(&self) -> TypeId

Gets the `TypeId` of `self`. Read more
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### impl<T> Borrow<T> for T
where T: ?Sized,

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#### fn borrow(&self) -> &T

Immutably borrows from an owned value. Read more
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### impl<T> BorrowMut<T> for T
where T: ?Sized,

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#### fn borrow_mut(&mut self) -> &mut T

Mutably borrows from an owned value. Read more
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### impl<T> From<T> for T

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#### fn from(t: T) -> T

Returns the argument unchanged.

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### impl<T, U> Into<U> for T
where U: From<T>,

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#### fn into(self) -> U

Calls `U::from(self)`.

That is, this conversion is whatever the implementation of `From<T> for U` chooses to do.

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### impl<T> ToString for T
where T: Display + ?Sized,

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#### default fn to_string(&self) -> String

Converts the given value to a `String`. Read more
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### impl<T, U> TryFrom<U> for T
where U: Into<T>,

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#### type Error = Infallible

The type returned in the event of a conversion error.
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#### fn try_from(value: U) -> Result<T, <T as TryFrom<U>>::Error>

Performs the conversion.
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### impl<T, U> TryInto<U> for T
where U: TryFrom<T>,

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

The type returned in the event of a conversion error.
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#### fn try_into(self) -> Result<U, <U as TryFrom<T>>::Error>

Performs the conversion.