--- sbbs/include/mozilla/js/jsbool.h	2018/04/24 16:41:23	1.1.1.1
+++ sbbs/include/mozilla/js/jsbool.h	2018/04/24 16:42:13	1.1.1.2
@@ -45,6 +45,20 @@
 
 JS_BEGIN_EXTERN_C
 
+/*
+ * Crypto-booleans, not visible to script but used internally by the engine.
+ *
+ * JSVAL_HOLE is a useful value for identifying a hole in an array.  It's also
+ * used in the interpreter to represent "no exception pending".  In general it
+ * can be used to represent "no value".
+ *
+ * JSVAL_ARETURN is used to throw asynchronous return for generator.close().
+ */
+#define JSVAL_HOLE      BOOLEAN_TO_JSVAL(2)
+#define JSVAL_ARETURN   BOOLEAN_TO_JSVAL(3)
+
+extern JSClass js_BooleanClass;
+
 extern JSObject *
 js_InitBooleanClass(JSContext *cx, JSObject *obj);