Struct BoxPredicate 

pub struct BoxPredicate<T> { /* private fields */ }

A Box-based predicate with single ownership.

This type is suitable for one-time use scenarios where the predicate does not need to be cloned or shared. Composition methods consume self, reflecting the single-ownership model.

Examples

use prism3_function::predicate::{Predicate, BoxPredicate};

let pred = BoxPredicate::new(|x: &i32| *x > 0);
assert!(pred.test(&5));

// Chaining consumes the predicate
let combined = pred.and(BoxPredicate::new(|x| x % 2 == 0));
assert!(combined.test(&4));

Author

Haixing Hu

Implementations

impl<T: 'static> BoxPredicate<T>

pub fn new<F>(f: F) -> Self

where F: Fn(&T) -> bool + 'static,

Creates a new predicate.

Wraps the provided closure in the appropriate smart pointer type for this predicate implementation.

pub fn new_with_name<F>(name: &str, f: F) -> Self

where F: Fn(&T) -> bool + 'static,

Creates a new named predicate.

Wraps the provided closure and assigns it a name, which is useful for debugging and logging purposes.

pub fn new_with_optional_name<F>(f: F, name: Option<String>) -> Self

where F: Fn(&T) -> bool + 'static,

Creates a new named predicate with an optional name.

Wraps the provided closure and assigns it an optional name.

pub fn name(&self) -> Option<&str>

Gets the name of this predicate.

Returns

Returns Some(&str) if a name was set, None otherwise.

pub fn set_name(&mut self, name: &str)

Sets the name of this predicate.

Parameters

• name - The name to set for this predicate

pub fn always_true() -> Self

Creates a predicate that always returns true.

Returns

A new BoxPredicate that always returns true.

pub fn always_false() -> Self

Creates a predicate that always returns false.

Returns

A new BoxPredicate that always returns false.

pub fn and<P>(self, other: P) -> BoxPredicate<T>

where P: Predicate<T> + 'static, T: 'static,

Returns a predicate that represents the logical AND of this predicate and another.

This method consumes self due to single-ownership semantics.

Parameters

• other - The other predicate to combine with.

Returns

A new predicate representing the logical AND.

pub fn or<P>(self, other: P) -> BoxPredicate<T>

where P: Predicate<T> + 'static, T: 'static,

Returns a predicate that represents the logical OR of this predicate and another.

This method consumes self due to single-ownership semantics.

Parameters

• other - The other predicate to combine with.

Returns

A new predicate representing the logical OR.

pub fn not(self) -> BoxPredicate<T>

where T: 'static,

Returns a predicate that represents the logical negation of this predicate.

This method consumes self due to single-ownership semantics.

Returns

A new predicate representing the logical negation.

pub fn nand<P>(self, other: P) -> BoxPredicate<T>

where P: Predicate<T> + 'static, T: 'static,

Returns a predicate that represents the logical NAND (NOT AND) of this predicate and another.

NAND returns true unless both predicates are true. Equivalent to !(self AND other).

This method consumes self due to single-ownership semantics.

Parameters

• other - The other predicate to combine with.

Returns

A new predicate representing the logical NAND.

pub fn xor<P>(self, other: P) -> BoxPredicate<T>

where P: Predicate<T> + 'static, T: 'static,

Returns a predicate that represents the logical XOR (exclusive OR) of this predicate and another.

XOR returns true if exactly one of the predicates is true.

This method consumes self due to single-ownership semantics.

Parameters

• other - The other predicate to combine with.

Returns

A new predicate representing the logical XOR.

pub fn nor<P>(self, other: P) -> BoxPredicate<T>

where P: Predicate<T> + 'static, T: 'static,

Returns a predicate that represents the logical NOR (NOT OR) of this predicate and another.

NOR returns true only when both predicates are false. Equivalent to !(self OR other).

This method consumes self due to single-ownership semantics.

Parameters

• other - The other predicate to combine with.

Returns

A new predicate representing the logical NOR.

Trait Implementations

impl<T> Debug for BoxPredicate<T>

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

Formats the value using the given formatter.

impl<T> Display for BoxPredicate<T>

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

Formats the value using the given formatter.

impl<T: 'static> Predicate<T> for BoxPredicate<T>

fn test(&self, value: &T) -> bool

Tests whether the given value satisfies this predicate.

fn into_box(self) -> BoxPredicate<T>

where T: 'static,

Converts this predicate into a BoxPredicate.

fn into_rc(self) -> RcPredicate<T>

where T: 'static,

Converts this predicate into an RcPredicate.

fn into_fn(self) -> impl Fn(&T) -> bool

Converts this predicate into a closure that can be used directly with standard library methods.

fn into_arc(self) -> ArcPredicate<T>

where Self: Sized + Send + Sync + 'static, T: 'static,

Converts this predicate into an ArcPredicate.