Crate phantomdrop

Small library for defering the running of function until the end of a block.

Uasge

Similar to the defer mechanism in Go, we can use this to defer the calling of functions

fn do_something()
{
  let _guard = phantomdrop::defer(|| println!("Hello!"));
  // do some work
} // "Hello!" will now be printed when the function returns or unwinds (unless unwinds are disabled).

The guard can also hold a value

fn do_something(print: String)
{
 let _guard = PhantomDrop::new(print, |string| println!("Dropped: {}", string));
 // do some work
} // `print` will now be printed here.

Or capture a value, by reference, mutable reference, or moving.

fn do_something(print: String)
{
 let _guard = phantomdrop::defer(move || println!("Dropped: {}", print)); // Moves `print` into itself.
 // do some work
} // `print` will now be printed here.

fn do_something_by_reference(print: String)
{
 let _guard = phantomdrop::defer(|| println!("Dropped: {}", print)); // Holds an immutable reference to `print`.
 let trimmed = print.trim(); // Can still be used
} // `print` will now be printed here.

fn do_something_by_mutable_reference(print: &mut String)
{
 let _guard = phantomdrop::defer(|| *print = String::from("Dropped")); // Holds a mutable reference to `print`.
} // `print` will now be set to "Dropped" here.

Structs

PhantomDrop

When dropped, the included function is ran with the argument held by the structure.

Functions

defer

Defer this function to run when the returned guard is dropped.