1 files changed, 7 insertions, 0 deletions
diff --git a/src/include/tree.h b/src/include/tree.h
index 3dfb5be..ba1f5a5 100644
--- a/src/include/tree.h
+++ b/src/include/tree.h
@@ -5,6 +5,7 @@
 
 typedef enum TREE_TYPE {
       TREE_TYPE_BLOCK,
+      TREE_TYPE_EXPR,
       TREE_TYPE_LINT,
       TREE_TYPE_LSTR,
       TREE_TYPE_TAG,
@@ -30,6 +31,12 @@ typedef struct TREE {
          struct TREE* nxt;
       } block;
 
+      /* Expression. */
+      struct TREE_DATA_EXPR {
+         /* The contents of the expression. */
+         struct TREE* val;
+      } expr;
+
       /* Literal integer. */
       struct TREE_DATA_LINT {
          int val;