Struct DropGuard 

pub struct DropGuard<T: Any> { /* private fields */ }

A smart pointer which automatically puts the contained object back into the Pool on drop.

This version is not thread-safe. For the thread-safe version take a look at SyncDropGuard.

Implementations

impl<T: Any> DropGuard<T>

pub fn new(obj: T, pool: &Pool) -> Self

Creates a new DropGuard from an abritrary object and adds the reference to a regular Pool.

Example

Creating a DropGuard yourself might be usefull if you want to use objects which you want to manually create, but where you still want to have the auto-adding to the pool once they go out of scope.

use generic_pool::{Pool, DropGuard};

struct Buffer(Vec<u8>);

impl Buffer {
    fn len(&self) -> usize {
        self.0.len()
    }
}

fn main() {
    let mut pool = Pool::new();

    // You use buffers which have a length of exactly 1kb.
    let buffer = match pool.get_with_guard::<Buffer>() {
        Some(buffer) => buffer,
        None => DropGuard::new(Buffer(vec![0u8; 1024]), &pool),
    };

    assert_eq!(buffer.len(), 1024);

    assert!(pool.get::<Buffer>().is_none());
    drop(buffer);
    let buffer = pool.get::<Buffer>().unwrap();
    assert_eq!(buffer.len(), 1024);
}

pub fn into_inner(guard: DropGuard<T>) -> T

Consume this guard and return the contained object.

Note that this is an associated function and not a method. See the example.

Example

use generic_pool::{Pool, DropGuard};

struct Buffer(Vec<u8>);

impl Buffer {
    fn len(&self) -> usize {
        self.0.len()
    }
}

fn main() {
    let mut pool = Pool::new();

    // You use buffers which have a length of exactly 1kb.
    let buffer = match pool.get_with_guard::<Buffer>() {
        Some(buffer) => buffer,
        None => DropGuard::new(Buffer(vec![0u8; 1024]), &pool),
    };

    // Maybe you want to use the buffer for something else.
    let buffer: Buffer = DropGuard::into_inner(buffer);
    let mut buffer: Vec<u8> = buffer.0;
    buffer.clear();

    assert_eq!(buffer.len(), 0);
}

Trait Implementations

impl<T: Any> AsMut<T> for DropGuard<T>

fn as_mut(&mut self) -> &mut T

Converts this type into a mutable reference of the (usually inferred) input type.

impl<T: Any> AsRef<T> for DropGuard<T>

fn as_ref(&self) -> &T

Converts this type into a shared reference of the (usually inferred) input type.

impl<T: Any + Clone> Clone for DropGuard<T>

fn clone(&self) -> Self

Returns a duplicate of the value.

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

Performs copy-assignment from source.

impl<T: Debug + Any> Debug for DropGuard<T>

fn fmt(&self, f: &mut Formatter<'_>) -> Result

Formats the value using the given formatter.

impl<T: Any> Deref for DropGuard<T>

type Target = T

The resulting type after dereferencing.

fn deref(&self) -> &Self::Target

Dereferences the value.

impl<T: Any> DerefMut for DropGuard<T>

fn deref_mut(&mut self) -> &mut Self::Target

Mutably dereferences the value.

impl<T: Any + Display> Display for DropGuard<T>

fn fmt(&self, f: &mut Formatter<'_>) -> Result

Formats the value using the given formatter.

impl<T: Any> Drop for DropGuard<T>

Ensures the contained value gets automatically added back to the Pool it came from.

fn drop(&mut self)

Executes the destructor for this type.

impl<T: Any + Hash> Hash for DropGuard<T>

The hash value corresponds to the hash value of the contained object.

fn hash<H: Hasher>(&self, state: &mut H)

Feeds this value into the given Hasher.

fn hash_slice<H>(data: &[Self], state: &mut H)

where H: Hasher, Self: Sized,

Feeds a slice of this type into the given Hasher.

impl<T: Any + Ord> Ord for DropGuard<T>

fn cmp(&self, other: &DropGuard<T>) -> Ordering

This method returns an Ordering between self and other.

fn max(self, other: Self) -> Self

where Self: Sized,

Compares and returns the maximum of two values.

fn min(self, other: Self) -> Self

where Self: Sized,

Compares and returns the minimum of two values.

fn clamp(self, min: Self, max: Self) -> Self

where Self: Sized,

Restrict a value to a certain interval.

impl<T: Any + PartialEq> PartialEq for DropGuard<T>

fn eq(&self, other: &DropGuard<T>) -> bool

Tests for self and other values to be equal, and is used by ==.

fn ne(&self, other: &Rhs) -> bool

Tests for !=. The default implementation is almost always sufficient, and should not be overridden without very good reason.

impl<T: Any + PartialOrd> PartialOrd for DropGuard<T>

fn partial_cmp(&self, other: &DropGuard<T>) -> Option<Ordering>

This method returns an ordering between self and other values if one exists.

fn lt(&self, other: &Rhs) -> bool

Tests less than (for self and other) and is used by the < operator.

fn le(&self, other: &Rhs) -> bool

Tests less than or equal to (for self and other) and is used by the <= operator.

fn gt(&self, other: &Rhs) -> bool

Tests greater than (for self and other) and is used by the > operator.

fn ge(&self, other: &Rhs) -> bool

Tests greater than or equal to (for self and other) and is used by the >= operator.

impl<T: Any + Eq> Eq for DropGuard<T>