modmath 0.5.0

Modular math implemented with traits.
Documentation 
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//! Schoolbook modular arithmetic with reference-based parameters
//! throughout — `Clone`, never `Copy`, so heap-allocated bigints
//! qualify.
//!
//! Uses `OverflowingAdd` / `OverflowingSub` rather than
//! `WrappingAdd` / `WrappingSub`, the strictest bound profile in the
//! toolbox. Suitable for backends that don't wrap on overflow —
//! arbitrary-precision types have no modulus-2^k to wrap at, but can
//! report overflow against a fixed working width.
//!
//! See [`modmath::basic`](crate::basic) (`Copy`-bound, simplest) and
//! [`modmath::constrained`](crate::constrained) (`Clone`-bound, mixed
//! value/reference) for less strict surfaces.
//!
//! ## Pre-reduced variants
//!
//! [`pre_reduced`] re-exports `add` / `sub` / `mul` / `exp` siblings that
//! assume inputs are already in `[0, m)` and skip the `% m` reduction
//! step. Works for backends without `core::ops::Rem` and is the right
//! entry point inside loops where reduction is handled separately.
//! Note: `inv` has no pre-reduced sibling — modular inverse via the
//! extended Euclidean algorithm inside `inv` performs its own
//! magnitude-dependent loop, with no useful "pre-reduced" shortcut.

#[doc(inline)]
pub use crate::add::strict_mod_add as add;
#[doc(inline)]
pub use crate::exp::strict_mod_exp as exp;
#[doc(inline)]
pub use crate::inv::strict_mod_inv as inv;
#[doc(inline)]
pub use crate::mul::strict_mod_mul as mul;
#[doc(inline)]
pub use crate::sub::strict_mod_sub as sub;

pub mod montgomery;

/// Pre-reduced variants. Caller guarantees inputs are in `[0, m)`;
/// no `Rem`-family bound.
pub mod pre_reduced {
    #[doc(inline)]
    pub use crate::add::strict_mod_add_pr as add;
    #[doc(inline)]
    pub use crate::exp::strict_mod_exp_pr as exp;
    #[doc(inline)]
    pub use crate::mul::strict_mod_mul_pr as mul;
    #[doc(inline)]
    pub use crate::sub::strict_mod_sub_pr as sub;
}

/// Non-zero-modulus variants. See [`basic::nonzero`](crate::basic::nonzero).
pub mod nonzero {
    #[doc(inline)]
    pub use crate::add::strict_mod_add_nz as add;
    #[doc(inline)]
    pub use crate::exp::strict_mod_exp_nz as exp;
    #[doc(inline)]
    pub use crate::mul::strict_mod_mul_nz as mul;
    #[doc(inline)]
    pub use crate::sub::strict_mod_sub_nz as sub;
}