diff --git a/code/compiler_ast.hpp b/code/compiler_ast.hpp
index ea3497d..e734d78 100644
--- a/code/compiler_ast.hpp
+++ b/code/compiler_ast.hpp
@@ -3,30 +3,13 @@
 #include <vector>
 
 struct ast {
-    virtual ~ast();
+    virtual ~ast() = default;
 };
 
 using ast_ptr = std::unique_ptr<ast>;
 
 struct pattern {
-    virtual ~pattern();
-};
-
-struct pattern_var : public pattern {
-    std::string var;
-
-    pattern_var(const char* v)
-        : var(v) {}
-};
-
-struct pattern_constr : public pattern {
-    std::string constr;
-    std::vector<std::string> params;
-
-    pattern_constr(const char* c, std::vector<std::string>&& p)
-        : constr(c) {
-        std::swap(params, p);
-    }
+    virtual ~pattern() = default;
 };
 
 using pattern_ptr = std::unique_ptr<pattern>;
@@ -35,12 +18,18 @@ struct branch {
     pattern_ptr pat;
     ast_ptr expr;
 
-    branch(pattern_ptr&& p, ast_ptr&& a)
+    branch(pattern_ptr p, ast_ptr a)
         : pat(std::move(p)), expr(std::move(a)) {}
 };
 
 using branch_ptr = std::unique_ptr<branch>;
 
+struct definition {
+    virtual ~definition() = default;
+};
+
+using definition_ptr = std::unique_ptr<definition>;
+
 enum binop {
     PLUS,
     MINUS,
@@ -48,12 +37,33 @@ enum binop {
     DIVIDE
 };
 
+struct ast_int : public ast {
+    int value;
+
+    explicit ast_int(int v)
+        : value(v) {}
+};
+
+struct ast_lid : public ast {
+    std::string id;
+
+    explicit ast_lid(std::string i)
+        : id(std::move(i)) {}
+};
+
+struct ast_uid : public ast {
+    std::string id;
+
+    explicit ast_uid(std::string i)
+        : id(std::move(i)) {}
+};
+
 struct ast_binop : public ast {
     binop op;  
     ast_ptr left;
     ast_ptr right;
 
-    ast_binop(binop o, ast_ptr&& l, ast_ptr&& r)
+    ast_binop(binop o, ast_ptr l, ast_ptr r)
         : op(o), left(std::move(l)), right(std::move(r)) {}
 };
 
@@ -61,16 +71,40 @@ struct ast_app : public ast {
     ast_ptr left;
     ast_ptr right;
 
-    ast_app(ast* l, ast* r)
-        : left(l), right(r) {}
+    ast_app(ast_ptr l, ast_ptr r)
+        : left(std::move(l)), right(std::move(r)) {}
 };
 
 struct ast_case : public ast {
     ast_ptr of;
     std::vector<branch_ptr> branches;
 
-    ast_case(ast_ptr&& o, std::vector<branch_ptr>&& b)
-        : of(std::move(o)) {
-        std::swap(branches, b);
+    ast_case(ast_ptr o, std::vector<branch_ptr> b)
+        : of(std::move(o)), branches(std::move(b)) {}
+};
+
+struct pattern_var : public pattern {
+    std::string var;
+
+    pattern_var(std::string v)
+        : var(std::move(v)) {}
+};
+
+struct pattern_constr : public pattern {
+    std::string constr;
+    std::vector<std::string> params;
+
+    pattern_constr(std::string c, std::vector<std::string> p)
+        : constr(std::move(c)), params(std::move(p)) {}
+};
+
+struct definition_defn : public definition {
+    std::string name;
+    std::vector<std::string> params;
+    ast_ptr body;
+
+    definition_defn(std::string n, std::vector<std::string> p, ast_ptr b)
+        : name(std::move(n)), params(std::move(p)), body(std::move(b)) {
+
     }
 };