Struct OnDrop

pub struct OnDrop<F: FnOnce()> { /* private fields */ }

A type which calls a function when dropped. This can be used to ensure that cleanup code is run even in case of a panic.

Note that this only works for panics that unwind – any code within OnDrop will be skipped if a panic does not unwind. In most cases, this will just work.

Examples

// This will print a message when the variable `_catch` gets dropped,
// even if a panic occurs before we reach the end of this scope.
// This is similar to a `try ... catch` block in languages such as C++.
let _catch = OnDrop::new(|| log("Oops, a panic occurred and this function didn't complete!"));

// Some code that may panic...
// ...

// Make sure the message only gets printed if a panic occurs.
// If we remove this line, then the message will be printed regardless of whether a panic occurs
// -- similar to a `try ... finally` block.
std::mem::forget(_catch);

Implementations

impl<F: FnOnce()> OnDrop<F>

pub fn new(callback: F) -> Self

Returns an object that will invoke the specified callback when dropped.

Trait Implementations

impl<F: FnOnce()> Drop for OnDrop<F>

fn drop(&mut self)

Executes the destructor for this type.