Struct Env 

pub struct Env {
    pub bindings: Rc<RefCell<HashMap<Spur, Value>>>,
    pub parent: Option<Rc<Env>>,
    pub version: Cell<u64>,
}

A Sema environment: a chain of scopes with bindings.

Fields

bindings: Rc<RefCell<HashMap<Spur, Value>>>

parent: Option<Rc<Env>>

version: Cell<u64>

Implementations

impl Env

pub fn new() -> Self

pub fn with_parent(parent: Rc<Env>) -> Self

pub fn bump_version(&self)

Bump the environment’s version counter. The VM’s inline global cache is keyed on this version, so call this after mutating bindings through a different Env handle that shares the same bindings Rc but has its own version cell (e.g. a loaded module body run on a cloned-Env VM), so a VM observing this Env re-reads instead of serving a stale cached value.

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

pub fn get_str(&self, name: &str) -> Option<Value>

pub fn set(&self, name: Spur, val: Value)

pub fn set_str(&self, name: &str, val: Value)

pub fn update(&self, name: Spur, val: Value)

Update a binding that already exists in the current scope.

pub fn take(&self, name: Spur) -> Option<Value>

Remove and return a binding from the current scope only.

pub fn take_anywhere(&self, name: Spur) -> Option<Value>

Remove and return a binding from any scope in the parent chain.

pub fn set_existing(&self, name: Spur, val: Value) -> bool

Set a variable in the scope where it’s defined (for set!).

pub fn all_names(&self) -> Vec<Spur>

Collect all bound variable names across all scopes (for suggestions).

pub fn iter_bindings(&self, f: impl FnMut(Spur, &Value))

Iterate over bindings in the current scope only (not parent scopes).

pub fn get_local(&self, name: Spur) -> Option<Value>

Get a binding from the current scope only (not parent scopes).

pub fn replace_bindings( &self, new_bindings: impl IntoIterator<Item = (Spur, Value)>, )

Replace all bindings in the current scope with the given iterator. Used for bulk restore (e.g., undo/rollback).

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() -> Self

Returns the “default value” for a type.