64 lines
1.4 KiB
Rust
64 lines
1.4 KiB
Rust
use rpds::HashTrieMapSync;
|
|
|
|
use crate::ty::common::Symbol;
|
|
use crate::ty::internal::Value;
|
|
|
|
pub struct Env {
|
|
last: Option<Box<Env>>,
|
|
map: HashTrieMapSync<Symbol, Value>,
|
|
}
|
|
|
|
#[derive(Debug, Clone)]
|
|
pub struct LockedEnv {
|
|
map: HashTrieMapSync<Symbol, Value>
|
|
}
|
|
|
|
impl Env {
|
|
pub fn empty() -> Env {
|
|
Env {
|
|
last: None,
|
|
map: HashTrieMapSync::new_sync(),
|
|
}
|
|
}
|
|
|
|
pub fn lookup(&self, symbol: Symbol) -> Option<Value> {
|
|
self.map.get(&symbol).cloned()
|
|
}
|
|
|
|
pub fn insert(&mut self, symbol: Symbol, value: Value) {
|
|
self.map.insert_mut(symbol, value);
|
|
}
|
|
|
|
pub fn enter(&mut self, new: HashTrieMapSync<Symbol, Value>) {
|
|
let mut map = self.map.clone();
|
|
for (k, v) in new.iter() {
|
|
map.insert_mut(k.clone(), v.clone());
|
|
}
|
|
let last = std::mem::replace(self, Env { last: None, map });
|
|
self.last = Some(Box::new(last));
|
|
}
|
|
|
|
pub fn leave(&mut self) {
|
|
let last = std::mem::replace(&mut self.last, None).unwrap();
|
|
let _ = std::mem::replace(&mut self.last, last.last);
|
|
self.map = last.map;
|
|
}
|
|
|
|
pub fn locked(&self) -> LockedEnv {
|
|
LockedEnv { map: self.map.clone() }
|
|
}
|
|
}
|
|
|
|
impl LockedEnv {
|
|
pub fn lookup(&self, symbol: Symbol) -> Option<Value> {
|
|
self.map.get(&symbol).cloned()
|
|
}
|
|
|
|
pub fn unlocked(self) -> Env {
|
|
Env {
|
|
map: self.map,
|
|
last: None
|
|
}
|
|
}
|
|
}
|