Struct OpClosure 

pub struct OpClosure<T, Op: Fn(T, T) -> T, Id: Fn() -> T>(/* private fields */);

任意の結合的な演算を持つ。

結合性については使用者側に保証してもらう。

Examples

use std::cell::RefCell;

use nekolib::traits::{Magma, Identity};
use nekolib::utils::OpClosure;

let runtime_mod = 10;
let op_memo = RefCell::new(vec![]);
let id_times = RefCell::new(0);
let op_cl = OpClosure::new(|x: i32, y| {
    op_memo.borrow_mut().push((x, y));
    (x + y).rem_euclid(runtime_mod)
}, || {
    *id_times.borrow_mut() += 1;
    0
});

assert_eq!(op_cl.op(1, 9), 0);
assert_eq!(op_cl.op(3, 8), 1);
assert_eq!(op_cl.op(-5, -3), 2);
assert_eq!(op_cl.id(), 0);

assert_eq!(*op_memo.borrow(), [(1, 9), (3, 8), (-5, -3)]);
assert_eq!(*id_times.borrow(), 1);

Implementations

impl<T: Eq, Op: Fn(T, T) -> T, Id: Fn() -> T> OpClosure<T, Op, Id>

pub fn new(op: Op, id: Id) -> Self

Trait Implementations

impl<T: Clone, Op: Clone + Fn(T, T) -> T, Id: Clone + Fn() -> T> Clone for OpClosure<T, Op, Id>

fn clone(&self) -> OpClosure<T, Op, Id>

Returns a duplicate of the value.

fn clone_from(&mut self, source: &Self)

Performs copy-assignment from source.

impl<T: Debug, Op: Debug + Fn(T, T) -> T, Id: Debug + Fn() -> T> Debug for OpClosure<T, Op, Id>

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

Formats the value using the given formatter.

impl<T: Default, Op: Default + Fn(T, T) -> T, Id: Default + Fn() -> T> Default for OpClosure<T, Op, Id>

fn default() -> OpClosure<T, Op, Id>

Returns the “default value” for a type.

impl<T: Eq, Op: Fn(T, T) -> T, Id: Fn() -> T> Identity for OpClosure<T, Op, Id>

fn id(&self) -> T

単位元を返す。

impl<T: Eq, Op: Fn(T, T) -> T, Id: Fn() -> T> Magma for OpClosure<T, Op, Id>

type Set = T

集合 $M$ に対応する型。

fn op(&self, lhs: T, rhs: T) -> T

$x \circ y$ を返す。

impl<T: Eq, Op: Fn(T, T) -> T, Id: Fn() -> T> Associative for OpClosure<T, Op, Id>

impl<T: Copy, Op: Copy + Fn(T, T) -> T, Id: Copy + Fn() -> T> Copy for OpClosure<T, Op, Id>