diff --git a/jlc/ASTNode.cc b/jlc/ASTNode.cc
new file mode 100644
index 0000000..df7ea5c
--- /dev/null
+++ b/jlc/ASTNode.cc
@@ -0,0 +1,15 @@
+
+#include "ASTNode.h"
+
+ASTNode::~ASTNode()
+{
+    /* clean up any children nodes */
+    int sz = myChildren.size();
+    for (int i = 0; i < sz; i++)
+        delete myChildren[i];
+}
+
+void ASTNode::addChild(ASTNode * node)
+{
+    myChildren.push_back(node);
+}
diff --git a/jlc/ASTNode.h b/jlc/ASTNode.h
new file mode 100644
index 0000000..dbc2aee
--- /dev/null
+++ b/jlc/ASTNode.h
@@ -0,0 +1,13 @@
+
+#include <vector>
+
+class ASTNode
+{
+public:
+    virtual ~ASTNode();
+    void    addChild(ASTNode * node);
+    std::vector<ASTNode *>  & getChildren() { return myChildren; }
+
+private:
+    std::vector<ASTNode *>  myChildren;
+};
diff --git a/jlc/Makefile b/jlc/Makefile
index c580011..d824754 100644
--- a/jlc/Makefile
+++ b/jlc/Makefile
@@ -7,6 +7,7 @@ LDFLAGS := -lfl
 
 COBJS := lex.yy.o
 CXXOBJS := $(TARGET).tab.o
+CXXOBJS += ASTNode.o
 
 all: $(TARGET)
 
diff --git a/jlc/jlc.yy b/jlc/jlc.yy
index d01d5be..be36d16 100644
--- a/jlc/jlc.yy
+++ b/jlc/jlc.yy
@@ -152,7 +152,7 @@ assignment: ID ASSIGN number SEMICOLON ;
 
 int main(int argc, char * argv[])
 {
-    if (argc > 0)
+    if (argc > 1)
     {
         yyin = fopen(argv[1], "r");
         if (yyin == NULL)