pub enum Steal<T> {
    Empty,
    Success(T),
    Retry,
}
Expand description

Possible outcomes of a steal operation.

Examples

There are lots of ways to chain results of steal operations together:

use crossbeam_deque::Steal::{self, Empty, Retry, Success};

let collect = |v: Vec<Steal<i32>>| v.into_iter().collect::<Steal<i32>>();

assert_eq!(collect(vec![Empty, Empty, Empty]), Empty);
assert_eq!(collect(vec![Empty, Retry, Empty]), Retry);
assert_eq!(collect(vec![Retry, Success(1), Empty]), Success(1));

assert_eq!(collect(vec![Empty, Empty]).or_else(|| Retry), Retry);
assert_eq!(collect(vec![Retry, Empty]).or_else(|| Success(1)), Success(1));

Variants

Empty

The queue was empty at the time of stealing.

Success(T)

At least one task was successfully stolen.

Retry

The steal operation needs to be retried.

Implementations

Returns true if the queue was empty at the time of stealing.

Examples
use crossbeam_deque::Steal::{Empty, Retry, Success};

assert!(!Success(7).is_empty());
assert!(!Retry::<i32>.is_empty());

assert!(Empty::<i32>.is_empty());

Returns true if at least one task was stolen.

Examples
use crossbeam_deque::Steal::{Empty, Retry, Success};

assert!(!Empty::<i32>.is_success());
assert!(!Retry::<i32>.is_success());

assert!(Success(7).is_success());

Returns true if the steal operation needs to be retried.

Examples
use crossbeam_deque::Steal::{Empty, Retry, Success};

assert!(!Empty::<i32>.is_retry());
assert!(!Success(7).is_retry());

assert!(Retry::<i32>.is_retry());

Returns the result of the operation, if successful.

Examples
use crossbeam_deque::Steal::{Empty, Retry, Success};

assert_eq!(Empty::<i32>.success(), None);
assert_eq!(Retry::<i32>.success(), None);

assert_eq!(Success(7).success(), Some(7));

If no task was stolen, attempts another steal operation.

Returns this steal result if it is Success. Otherwise, closure f is invoked and then:

  • If the second steal resulted in Success, it is returned.
  • If both steals were unsuccessful but any resulted in Retry, then Retry is returned.
  • If both resulted in None, then None is returned.
Examples
use crossbeam_deque::Steal::{Empty, Retry, Success};

assert_eq!(Success(1).or_else(|| Success(2)), Success(1));
assert_eq!(Retry.or_else(|| Success(2)), Success(2));

assert_eq!(Retry.or_else(|| Empty), Retry::<i32>);
assert_eq!(Empty.or_else(|| Retry), Retry::<i32>);

assert_eq!(Empty.or_else(|| Empty), Empty::<i32>);

Trait Implementations

Returns a copy of the value. Read more
Performs copy-assignment from source. Read more
Formats the value using the given formatter. Read more

Consumes items until a Success is found and returns it.

If no Success was found, but there was at least one Retry, then returns Retry. Otherwise, Empty is returned.

This method tests for self and other values to be equal, and is used by ==. Read more
This method tests for !=. The default implementation is almost always sufficient, and should not be overridden without very good reason. Read more

Auto Trait Implementations

Blanket Implementations

Gets the TypeId of self. Read more
Immutably borrows from an owned value. Read more
Mutably borrows from an owned value. Read more

Returns the argument unchanged.

Calls U::from(self).

That is, this conversion is whatever the implementation of [From]<T> for U chooses to do.

The alignment of pointer.
The type for initializers.
Initializes a with the given initializer. Read more
Dereferences the given pointer. Read more
Mutably dereferences the given pointer. Read more
Drops the object pointed to by the given pointer. Read more
The resulting type after obtaining ownership.
Creates owned data from borrowed data, usually by cloning. Read more
Uses borrowed data to replace owned data, usually by cloning. Read more
The type returned in the event of a conversion error.
Performs the conversion.
The type returned in the event of a conversion error.
Performs the conversion.