pub trait PredicateBoxExt<Item: ?Sized>where
    Self: Predicate<Item>,{
    // Provided method
    fn boxed(self) -> BoxPredicate<Item>
       where Self: Sized + Send + Sync + 'static { ... }
Expand description

Predicate extension for boxing a Predicate.

Provided Methods§


fn boxed(self) -> BoxPredicate<Item>where Self: Sized + Send + Sync + 'static,

Returns a BoxPredicate wrapper around this Predicate type.

Returns a BoxPredicate wrapper around this Predicate type. The BoxPredicate` type has a number of useful properties:

  • It stores the inner predicate as a trait object, so the type of BoxPredicate will always be the same even if steps are added or removed from the predicate.
  • It is a common type, allowing it to be stored in vectors or other collection types.
  • It implements Debug and Display.
use predicates::prelude::*;

let predicates = vec![
assert_eq!(true, predicates[0].eval(&4));
assert_eq!(false, predicates[1].eval(&4));



impl<P, Item> PredicateBoxExt<Item> for Pwhere P: Predicate<Item>,