Struct Env 

pub struct Env { /* private fields */ }

A lexical environment: a frame of symbol bindings chained to a parent.

Lookups walk from the local frame outward through parent frames. The active Env is held by the Cx and swapped during nested scopes.

Implementations

impl Env

pub fn child(parent: Arc<Env>) -> Self

Builds a child environment with an empty frame over parent.

pub fn define(&mut self, name: Symbol, value: Value) -> Option<Value>

Binds a name in the local frame, returning any previous binding.

pub fn get(&self, name: &Symbol) -> Option<Value>

Looks up a name, walking outward to parent frames.

Trait Implementations

impl Clone for Env

fn clone(&self) -> Env

Returns a duplicate of the value.

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

Performs copy-assignment from source.

impl Debug for Env

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

Formats the value using the given formatter.

impl Default for Env

fn default() -> Env

Returns the “default value” for a type.