Question about direct proxies syncing their targets

[Tab Atkins Jr.]

In the direct proxies proposal at
<http://wiki.ecmascript.org/doku.php?id=harmony:direct_proxies>,
there's the following line:

get:
 * Invariant checks:
    * if property exists on target as a data property, updates the
target’s property with the returned value

Consider an xrange object like from Python, which represents a numeric
range (with a start, stop, and step) and exposes both an iterator and
get traps.

Am I correct in assuming that, since the target of an xrange proxy is
an empty object, iterating through the xrange or getting specific
values from it will *not* fill up the target in an attempt to
synchronize it with the returned values from the get trap?

~TJ