1 files changed, 40 insertions, 2 deletions
diff --git a/src/lib/sexpr.rs b/src/lib/sexpr.rs
index 0d37332..a6fbe49 100644
--- a/src/lib/sexpr.rs
+++ b/src/lib/sexpr.rs
@@ -1,7 +1,45 @@
 use super::types::Type;
 
-pub enum SEXP {
+#[derive(PartialEq, Debug)]
+pub enum SExpr {
     Atom(Type),
-    List(Vec<SEXP>)
+    Sexpr(Vec<SExpr>)
 }
 
+#[test]
+fn construct() {
+    let atom1 = SExpr::Atom(Type::Number(Number::Int(1)));
+    let atom2 = SExpr::Atom(Type::Number(Number::Int(2)));
+    let atom3 = SExpr::Atom(Type::Number(Number::Int(3)));
+    let atom4 = SExpr::Atom(Type::Number(Number::Int(4)));
+    let sexp = SExpr::Sexpr(vec!(atom1, atom2, atom3, atom4));
+    match sexp {
+        SExpr::Sexpr(ref x) => {
+            assert_eq!(x[0], SExpr::Atom(Type::Number(Number::Int(1))));
+        },
+        _ => panic!("What")
+    }
+}
+
+#[test]
+fn mutability() {
+    let atom1 = SExpr::Atom(Type::Number(Number::Int(1)));
+    let atom2 = SExpr::Atom(Type::Number(Number::Int(2)));
+    let atom3 = SExpr::Atom(Type::Number(Number::Int(3)));
+    let atom4 = SExpr::Atom(Type::Number(Number::Int(4)));
+    let mut sexp = SExpr::Sexpr(vec!(atom1, atom2, atom3, atom4));
+    match sexp {
+        SExpr::Sexpr(ref mut x) => match x[0] {
+            SExpr::Atom(Type::Number(Number::Int(ref mut x))) => *x += 7,
+            _ => panic!("What")
+        },
+        _ => panic!("What")
+    }
+
+    match sexp {
+        SExpr::Sexpr(ref x) => {
+            assert_eq!(x[0], SExpr::Atom(Type::Number(Number::Int(8))));
+        },
+        _ => panic!("What")
+    }
+}