deep_causality_algebra 0.1.0

Abstract algebra traits (groups, rings, fields, algebras) and isomorphism markers for deep_causality.
Documentation 
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/*
 * SPDX-License-Identifier: MIT
 * Copyright (c) 2023 - 2026. The DeepCausality Authors and Contributors. All Rights Reserved.
 */

//! `Count(u64)` — the additive count monoid (the `AggregateLogic::Some(k)` carrier: fold then
//! threshold). Commutative but NOT idempotent, so deliberately not a `BoundedSemilattice`.

use crate::{CommutativeMonoid, Monoid};

/// The count monoid `(ℕ, +, 0)`: identity `0`, `combine = +`. Commutative, not idempotent.
#[derive(Debug, Clone, Copy, PartialEq, Eq)]
pub struct Count(pub u64);

impl Monoid for Count {
    #[inline]
    fn empty() -> Self {
        Count(0)
    }
    #[inline]
    fn combine(self, other: Self) -> Self {
        Count(self.0 + other.0)
    }
}
impl CommutativeMonoid for Count {}
// Deliberately NOT `Idempotent`/`BoundedSemilattice`: `Count(1).combine(Count(1)) = Count(2) ≠ Count(1)`.