Struct RcLazyConfig 

pub struct RcLazyConfig;

Single-threaded memoization using Rc<LazyCell>.

Not thread-safe. Use ArcLazyConfig for multi-threaded contexts.

Trait Implementations

impl LazyConfig for RcLazyConfig

fn lazy_new<'a, A: 'a>(f: Box<Self::Thunk<'a, A>>) -> Self::Lazy<'a, A>

Creates a new lazy cell from an initializer.

Type Signature

forall self a. self a -> self a

Type Parameters

• 'a: The lifetime of the computation.
• A: The type of the value.

Parameters

• f: The initializer thunk.

Returns

A new lazy cell.

Examples

use fp_library::types::*;

let lazy = RcLazyConfig::lazy_new(Box::new(|| 42));
assert_eq!(*RcLazyConfig::evaluate(&lazy), 42);

fn try_lazy_new<'a, A: 'a, E: 'a>( f: Box<Self::TryThunk<'a, A, E>>, ) -> Self::TryLazy<'a, A, E>

Creates a new fallible lazy cell from an initializer.

Type Signature

forall self a e. self a e -> self a e

Type Parameters

• 'a: The lifetime of the computation.
• A: The type of the value.
• E: The type of the error.

Parameters

• f: The initializer thunk.

Returns

A new fallible lazy cell.

Examples

use fp_library::types::*;

let lazy = RcLazyConfig::try_lazy_new(Box::new(|| Ok::<i32, ()>(42)));
assert_eq!(RcLazyConfig::try_evaluate(&lazy), Ok(&42));

fn evaluate<'a, 'b, A: 'a>(lazy: &'b Self::Lazy<'a, A>) -> &'b A

Forces evaluation and returns a reference.

Type Signature

forall self a. self a -> a

Type Parameters

• 'a: The lifetime of the computation.
• 'b: The lifetime of the reference.
• A: The type of the value.

Parameters

• lazy: The lazy cell to evaluate.

Returns

A reference to the value.

Examples

use fp_library::types::*;

let lazy = RcLazyConfig::lazy_new(Box::new(|| 42));
assert_eq!(*RcLazyConfig::evaluate(&lazy), 42);

fn try_evaluate<'a, 'b, A: 'a, E: 'a>( lazy: &'b Self::TryLazy<'a, A, E>, ) -> Result<&'b A, &'b E>

Forces evaluation and returns a reference to the result.

Type Signature

forall self a e. self a e -> Result a e

Type Parameters

• 'a: The lifetime of the computation.
• 'b: The lifetime of the reference.
• A: The type of the value.
• E: The type of the error.

Parameters

• lazy: The fallible lazy cell to evaluate.

Returns

A result containing a reference to the value or error.

Examples

use fp_library::types::*;

let lazy = RcLazyConfig::try_lazy_new(Box::new(|| Ok::<i32, ()>(42)));
assert_eq!(RcLazyConfig::try_evaluate(&lazy), Ok(&42));

type Lazy<'a, A: 'a> = Rc<LazyCell<A, Box<dyn FnOnce() -> A + 'a>>>

The lazy cell type for infallible memoization.

type TryLazy<'a, A: 'a, E: 'a> = Rc<LazyCell<Result<A, E>, Box<dyn FnOnce() -> Result<A, E> + 'a>>>

The lazy cell type for fallible memoization.

type Thunk<'a, A: 'a> = dyn FnOnce() -> A + 'a

The type of the initializer thunk.

type TryThunk<'a, A: 'a, E: 'a> = dyn FnOnce() -> Result<A, E> + 'a

The type of the fallible initializer thunk.