Add ARRAY_SIZE macro, and use it where possible.
diff --git a/py/misc.h b/py/misc.h
index 002a97f..bf31f75 100644
--- a/py/misc.h
+++ b/py/misc.h
@@ -52,6 +52,11 @@
 int m_get_current_bytes_allocated(void);
 int m_get_peak_bytes_allocated(void);
 
+/** array helpers ***********************************************/
+
+// get the number of elements in a fixed-size array
+#define ARRAY_SIZE(a) (sizeof(a) / sizeof((a)[0]))
+
 /** unichar / UTF-8 *********************************************/
 
 typedef int unichar; // TODO