Expand description
Small library for defer
ing 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).
§Values
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§
- Phantom
Drop - 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.
Type Aliases§
- Phantom
Drop Empty PhantomDrop
with no associated data.- Phantom
Drop Pure PhantomDrop
that does not capture.