Offchain scaffolding.

offchain/src/compiler/ast.rs

@@ -0,0 +1,15 @@
+#[derive(Debug, Clone)]
+pub enum Expr {
+    IntLiteral(i32),
+    Instruction(InstructionKind, Vec<Expr>),
+    // You might have a variant for sublists if needed,
+    // or keep it all in the same structure.
+}
+
+#[derive(Debug, Clone)]
+pub enum InstructionKind {
+    // e.g. Plus, Minus, Mult, etc.
+    Plus,
+    Minus,
+    Mult,
+}