implement subshell, and fix vector operator[] unvalid index

1 files changed, 3 insertions, 0 deletions

diff --git a/include/lexer/ast.h b/include/lexer/ast.h
index d4b0fd5..871afaf 100644
--- a/include/lexer/ast.h
+++ b/include/lexer/ast.h
@@ -21,6 +21,9 @@ public:
     size_t left = string::npos;
     size_t right = string::npos;
 
+    // if this is marked as `subshell`
+    // it will fork a subshell
+    // then the subshell will handler the rest
     bool subshell;
 };