Error out on parser failure

1 files changed, 11 insertions, 0 deletions

diff --git a/input.lisp b/input.lisp
index e28e73a..100baa5 100644
--- a/input.lisp
+++ b/input.lisp
@@ -18,3 +18,14 @@
 
 (defun cursor-distance (input1 input2)
   (- (input-cursor input1) (input-cursor input2)))
+
+(defun line-and-column (input)
+  (let ((line 1) (column 1))
+    (dotimes (i (input-cursor input))
+      (let ((c (char (input-data input) i)))
+        (case c
+          (#\Newline
+           (incf line)
+           (setf column 1))
+          (t (incf column)))))
+    (values line column)))