pub struct DoOnceSync(_);
Expand description

A simple primitive for ensuring something is done exactly once. DoOnceSync is thread-safe and uses internal mutability, so you can do_once with an immutable reference.

e.g.

let once_task = DoOnceSync::new();
loop {
    once_task.do_once(|| {
        // this closure only runs once
    });
    //...
}

Implementations

The passed closure will be called only once, after that calling this will be a no-op.

Returns true if the task has been run once already

Trait Implementations

Auto Trait Implementations

Blanket Implementations

Gets the TypeId of self. Read more

Immutably borrows from an owned value. Read more

Mutably borrows from an owned value. Read more

Returns the argument unchanged.

Calls U::from(self).

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

The alignment of pointer.

The type for initializers.

Initializes a with the given initializer. Read more

Dereferences the given pointer. Read more

Mutably dereferences the given pointer. Read more

Drops the object pointed to by the given pointer. Read more

The type returned in the event of a conversion error.

Performs the conversion.

The type returned in the event of a conversion error.

Performs the conversion.