1 files changed, 9 insertions, 4 deletions
diff --git a/src/driver.c b/src/driver.c
index c9ac098..8902a55 100644
--- a/src/driver.c
+++ b/src/driver.c
@@ -21,17 +21,22 @@ static int interpret_file(const char *path) {
 
 int main(int argc, char **argv) {
   int opt;
-  while ((opt = getopt(argc, argv, "i:h")) != -1) {
-    switch (opt){
+  while ((opt = getopt(argc, argv, "i:a:h")) != -1) {
+    switch (opt) {
     case 'i': 
       interpret_file(optarg);
       return EXIT_SUCCESS;
+    case 'a':
+      print_ast_file(optarg);
+      return EXIT_SUCCESS;
     case 'h':
     default:
       fprintf(stderr, 
-        "Usage: %s [-i program.imp]\n"
+        "Usage: %s [ARGS]\n"
+        "  (no args)          start REPL\n"
         "  -i <program.imp>   interpret program and exit\n"
-        "  (no args)          start REPL\n",
+        "  -a <program.imp>   print ast\n"
+        "  -h                 print this message\n",
         argv[0]);
       return (opt == 'h') ? EXIT_SUCCESS : EXIT_FAILURE;
     }