diff --git a/jlc/jl.lex b/jlc/jl.lex
index cd4d964..0a1e0cc 100644
--- a/jlc/jl.lex
+++ b/jlc/jl.lex
@@ -5,8 +5,8 @@
 
 %%
 0b[01]+             return BIN_NUMBER;
-0x[0-9A-Fa-f]       return HEX_NUMBER;
-0[0-9]*             return OCT_NUMBER;
+0x[0-9A-Fa-f]+      return HEX_NUMBER;
+0[0-7]*             return OCT_NUMBER;
 [1-9][0-9]*         return DEC_NUMBER;
 \n                  /* ignore newlines */
 [ \t\v]             /* ignore whitespace */
diff --git a/jlc/jl.y b/jlc/jl.y
index 54ee106..3504c55 100644
--- a/jlc/jl.y
+++ b/jlc/jl.y
@@ -2,6 +2,8 @@
 %{
 #include <stdio.h>
 
+extern FILE * yyin;
+
 void yyerror(const char * str)
 {
     fprintf(stderr, "error: %s\n", str);
@@ -12,8 +14,12 @@ int yywrap()
     return 1;
 }
 
-main()
+int main(int argc, char * argv[])
 {
+    if (argc > 0)
+    {
+        yyin = fopen(argv[1], "r");
+    }
     yyparse();
 }
 
@@ -23,6 +29,9 @@ main()
 
 %%
 
+program: /* empty */
+       | number program { printf("Saw a number\n"); }
+
 number: BIN_NUMBER
       | OCT_NUMBER
       | DEC_NUMBER