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authorGriffin Smith <grfn@gws.fyi>2021-04-11T21·53-0400
committerglittershark <grfn@gws.fyi>2021-04-12T14·45+0000
commit6266c5d32f9ff651fcfc3a4cc0c68e89da56ca65 (patch)
tree5be3967585787c4456e17cb29423770217fdcede /users/grfn/achilles/src/common/env.rs
parent968effb5dc1a4617a0dceaffc70e986abe300c6e (diff)
refactor(users/glittershark): Rename to grfn r/2485
Rename my //users directory and all places that refer to glittershark to
grfn, including nix references and documentation.

This may require some extra attention inside of gerrit's database after
it lands to allow me to actually push things.

Change-Id: I4728b7ec2c60024392c1c1fa6e0d4a59b3e266fa
Reviewed-on: https://cl.tvl.fyi/c/depot/+/2933
Tested-by: BuildkiteCI
Reviewed-by: tazjin <mail@tazj.in>
Reviewed-by: lukegb <lukegb@tvl.fyi>
Reviewed-by: glittershark <grfn@gws.fyi>
Diffstat (limited to 'users/grfn/achilles/src/common/env.rs')
-rw-r--r--users/grfn/achilles/src/common/env.rs59
1 files changed, 59 insertions, 0 deletions
diff --git a/users/grfn/achilles/src/common/env.rs b/users/grfn/achilles/src/common/env.rs
new file mode 100644
index 000000000000..59a5e46c466f
--- /dev/null
+++ b/users/grfn/achilles/src/common/env.rs
@@ -0,0 +1,59 @@
+use std::borrow::Borrow;
+use std::collections::HashMap;
+use std::hash::Hash;
+use std::mem;
+
+/// A lexical environment
+#[derive(Debug, PartialEq, Eq)]
+pub struct Env<K: Eq + Hash, V>(Vec<HashMap<K, V>>);
+
+impl<K, V> Default for Env<K, V>
+where
+    K: Eq + Hash,
+{
+    fn default() -> Self {
+        Self::new()
+    }
+}
+
+impl<K, V> Env<K, V>
+where
+    K: Eq + Hash,
+{
+    pub fn new() -> Self {
+        Self(vec![Default::default()])
+    }
+
+    pub fn push(&mut self) {
+        self.0.push(Default::default());
+    }
+
+    pub fn pop(&mut self) {
+        self.0.pop();
+    }
+
+    pub fn save(&mut self) -> Self {
+        mem::take(self)
+    }
+
+    pub fn restore(&mut self, saved: Self) {
+        *self = saved;
+    }
+
+    pub fn set(&mut self, k: K, v: V) {
+        self.0.last_mut().unwrap().insert(k, v);
+    }
+
+    pub fn resolve<'a, Q>(&'a self, k: &Q) -> Option<&'a V>
+    where
+        K: Borrow<Q>,
+        Q: Hash + Eq + ?Sized,
+    {
+        for ctx in self.0.iter().rev() {
+            if let Some(res) = ctx.get(k) {
+                return Some(res);
+            }
+        }
+        None
+    }
+}