1 files changed, 7 insertions, 0 deletions
diff --git a/include/ast.h b/include/ast.h
index 0c34d0b..c45d4aa 100644
--- a/include/ast.h
+++ b/include/ast.h
@@ -132,6 +132,12 @@ struct Scope {
     FunctionSignature *function_signature; /* Borrowed from FunctionDecl. Only used if the scope belongs to FunctionDecl */
 };
 
+typedef enum {
+    VARIABLE_TYPE_FLAG_NONE      = 0,
+    VARIABLE_TYPE_FLAG_OPTIONAL  = 1 << 0,
+    VARIABLE_TYPE_FLAG_BORROW    = 1 << 1
+} VariableTypeFlag;
+
 typedef struct {
     enum {
         VARIABLE_TYPE_NONE,
@@ -143,6 +149,7 @@ typedef struct {
         Variable *variable;
         FunctionSignature *signature;
     } value;
+    VariableTypeFlag variable_type_flags;
 } VariableType;
 
 struct FileScopeReference {