Struct Substitution 

pub struct Substitution { /* private fields */ }

A substitution mapping bound variable levels to replacement expressions.

Allows performing multiple substitutions in a single pass over the expression.

Implementations

impl Substitution

pub fn new() -> Self

Create an empty substitution.

pub fn single(expr: Expr) -> Self

Create a substitution that maps BVar(0) to a single expression.

pub fn add(&mut self, level: usize, expr: Expr)

Add an entry: map BVar at level to expr.

pub fn get(&self, level: u32) -> Option<&Expr>

Get the replacement for BVar at level (if any).

pub fn len(&self) -> usize

The number of levels this substitution covers.

pub fn is_empty(&self) -> bool

Check if this substitution is empty.

pub fn apply(&self, expr: &Expr) -> Expr

Apply this substitution to an expression.

Trait Implementations

impl Clone for Substitution

fn clone(&self) -> Substitution

Returns a duplicate of the value.

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

Performs copy-assignment from source.

impl Debug for Substitution

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

Formats the value using the given formatter.

impl Default for Substitution

fn default() -> Substitution

Returns the “default value” for a type.