hackc: exit on invalid token

2 files changed, 16 insertions, 0 deletions

diff --git a/projects/hackc/parser.py b/projects/hackc/parser.py
index c3056d7..400b096 100644
--- a/projects/hackc/parser.py
+++ b/projects/hackc/parser.py
@@ -1,4 +1,5 @@
 from .tokens import Token
+from .utils import *
 
 KEYWORDS = [
     "class",
@@ -83,3 +84,9 @@ class Parser:
                 if token is not None:
                     self.tokens.append(token)
                     pos += token.length()
+                else:
+                    # invalid token
+                    print_err(f"{self._fp}:{line_no + 1}")
+                    print_err(line)
+                    print_err(" " * pos + f"^ Invalid token")
+                    exit(EXIT_CODE_INVALID_TOKEN)
diff --git a/projects/hackc/utils.py b/projects/hackc/utils.py
new file mode 100644
index 0000000..d1ea3ca
--- /dev/null
+++ b/projects/hackc/utils.py
@@ -0,0 +1,9 @@
+from sys import stderr
+
+EXIT_CODE_FILE_ERROR = 1
+EXIT_CODE_INVALID_TOKEN = 2
+EXIT_CODE_SYNTAX_ERROR = 4
+
+
+def print_err(msg):
+    print(msg, file=stderr)