Struct Perm 

pub struct Perm { /* private fields */ }

A literal permutation that respects negation: σ(¬l) = ¬σ(l). Represented by the image of each variable’s positive literal, so the negation invariant holds by construction.

Implementations

impl Perm

pub fn identity(num_vars: usize) -> Perm

The identity permutation over num_vars variables.

pub fn from_images(images: Vec<Lit>) -> Perm

Build from the image of each positive literal: images[v] = σ(+v).

pub fn apply(&self, l: Lit) -> Lit

Apply σ to a literal, respecting sign: σ(¬l) = ¬σ(l).

pub fn apply_clause(&self, clause: &[Lit]) -> Vec<Lit>

Apply σ to every literal of a clause.

pub fn num_vars(&self) -> usize

The number of variables the permutation is defined over.

pub fn is_identity(&self) -> bool

Whether this is the identity permutation.

pub fn extended(&self, nv: usize) -> Perm

Extend to nv variables, acting as the identity on the new (higher-indexed) variables. Used to lift a base-formula symmetry over auxiliary variables it does not touch.

pub fn compose(&self, other: &Perm) -> Perm

Compose: (self ∘ other)(l) = self(other(l)) — apply other first, then self.

Trait Implementations

impl Clone for Perm

fn clone(&self) -> Perm

Returns a duplicate of the value.

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

Performs copy-assignment from source.

impl Debug for Perm

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

Formats the value using the given formatter.

impl Hash for Perm

fn hash<__H: Hasher>(&self, state: &mut __H)

Feeds this value into the given Hasher.

fn hash_slice<H>(data: &[Self], state: &mut H)

where H: Hasher, Self: Sized,

Feeds a slice of this type into the given Hasher.

impl PartialEq for Perm

fn eq(&self, other: &Perm) -> bool

Tests for self and other values to be equal, and is used by ==.

fn ne(&self, other: &Rhs) -> bool

Tests for !=. The default implementation is almost always sufficient, and should not be overridden without very good reason.

impl Eq for Perm

impl StructuralPartialEq for Perm