py, lexer: Add allocation policy config; return NULL if can't allocate.
diff --git a/py/mpconfig.h b/py/mpconfig.h
index 73ecc92..a7e1c4a 100644
--- a/py/mpconfig.h
+++ b/py/mpconfig.h
@@ -36,6 +36,16 @@
/*****************************************************************************/
/* Memory allocation policy */
+// Initial amount for lexer indentation level
+#ifndef MP_ALLOC_LEXER_INDENT_INIT
+#define MP_ALLOC_LEXER_INDENT_INIT (10)
+#endif
+
+// Increment for lexer indentation level
+#ifndef MP_ALLOC_LEXEL_INDENT_INC
+#define MP_ALLOC_LEXEL_INDENT_INC (8)
+#endif
+
// Initial amount for parse rule stack
#ifndef MP_ALLOC_PARSE_RULE_INIT
#define MP_ALLOC_PARSE_RULE_INIT (64)