Some basic parsing works (fixing order of operations), and one test case.

src/syntax/ast.rs

@@ -1,21 +1,25 @@
 use crate::syntax::token_stream::Location;
 
+#[derive(Debug, PartialEq)]
 pub struct Program {
-   pub statements: Vec<Statement>,
-   pub result: Expression, 
+    pub statements: Vec<Statement>,
+    pub result: Expression,
 }
 
+#[derive(Debug, PartialEq)]
 pub enum Statement {
     Binding(Location, String, Expression),
     Expr(Location, Expression),
 }
 
+#[derive(Debug, PartialEq)]
 pub enum Expression {
     Value(Location, Value),
     Reference(Location, String),
     Primitive(Location, String, Vec<Expression>),
 }
 
+#[derive(Debug, PartialEq)]
 pub enum Value {
-    Number(Option<u8>, i128)
+    Number(Option<u8>, i128),
 }