diff --git a/src/ops.c b/src/ops.c
index 87fb2a0..48d629d 100644
--- a/src/ops.c
+++ b/src/ops.c
@@ -82,7 +82,7 @@
     {
 	if (opchars[i][0] == char1 && opchars[i][1] == char2)
 	    break;
-	if (i == (int)(sizeof(opchars) / sizeof(char [3]) - 1))
+	if (i == (int)ARRAY_LENGTH(opchars) - 1)
 	{
 	    internal_error("get_op_type()");
 	    break;