Struct function_cache::CachedFunction

pub struct CachedFunction<TFunction, TInput, TReturn> where
    TFunction: Fn(TInput) -> TReturn,
    TInput: Eq + Hash + Copy,
    TReturn: Copy,  { /* fields omitted */ }

Wraps an immutable function such that the results of its invocation are cached to a HashMap<TInput, TReturn>.

Implementations

impl<TFunction, TInput, TReturn> CachedFunction<TFunction, TInput, TReturn> where
    TFunction: Fn(TInput) -> TReturn,
    TInput: Eq + Hash + Copy,
    TReturn: Copy, 

pub fn new(function: TFunction) -> CachedFunction<TFunction, TInput, TReturn>

Returns a CachedFunction<TFunction, TInput, TReturn> that wraps the input function.

Arguments

• function - The function to wrap in a cache.

Examples

use std::thread;
use std::time::Duration;
use function_cache::CachedFunction;
 
let mut cached_function = CachedFunction::new(|x: i32| {
    thread::sleep(Duration::from_secs(2));
    x
});

pub fn value(&mut self, arg: TInput) -> TReturn

Gets the value of evaluating the function with the arg as input. First, the cache is checked and if the value with arg has already be computed, it will be returned from the cache.

Arguments

• arg - The argument to the function call.