Struct DropFlag

pub struct DropFlag<'frame> { /* private fields */ }

A drop flag, for tracking successful destruction.

A DropFlag is a reference to a counter somewhere on the stack that lives adjacent to storage for some value. It is just a counter: unsafe code is expected to associate semantic meaning to it.

A flag with a value of zero is usually called “dead”, and setting a flag to the dead state is called clearing it.

See the module documentation for more information.

Implementations

impl DropFlag<'_>

pub fn inc(self)

Increments the internal counter.

This function does not provide any overflow protection; unsafe code is responsible for making sure that cannot happen.

pub fn dec_and_check_if_died(self) -> bool

Decrements the internal counter and returns true if it became zero.

This function will return false if the counter was already zero.

pub fn is_dead(self) -> bool

Returns whether the internal counter is zero.

Trait Implementations

impl<'frame> Clone for DropFlag<'frame>

fn clone(&self) -> DropFlag<'frame>

Returns a copy of the value.

fn clone_from(&mut self, source: &Self)

Performs copy-assignment from source.

impl<'frame> Copy for DropFlag<'frame>