In-progress: Switch to proper AST

use-based-refs/interpreter/src/lib.rs

@@ -6,6 +6,16 @@ mod parser;
 
 pub use eval::eval;
 
+/// A Node of the λ_UR AST, simplified from the UrParser.
+// TODO: Switch to this vor eval
+pub enum Node {
+    Num(u32),
+    Unit,
+    Seq(Vec<Node>),
+    Let{ident: String, expr: Box<Expr>},
+    Lookup(String),
+}
+
 // TODO: Put this elsewhere?
 #[derive(Debug, PartialEq, Eq, Clone)]
 pub enum Value {

use-based-refs/interpreter/src/parser.rs

@@ -12,3 +12,11 @@ pub fn tokenize(input: &str) -> Result<Pair<'_, Rule>, String> {
         Err(e) => Err(format!("{e}")),
     }
 }
+
+
+// TODO: Fill
+pub fn ast(input: &str) -> Node {
+    match tokenize(input).as_rule() {
+
+    }
+}