[Harmony Proxies] get/set trap receiver argument unnecessary

Sean Eagan seaneagan1 at gmail.com
Wed Apr 27 10:38:02 PDT 2011


Hi,

The "get" and "set" traps currently have both "receiver" and "proxy"
arguments.  This is because it has been suggested that they are not
the same in the case of property access on a receiver causing a
[[Get]] / [[Put]] call to propogate up the prototype chain to a proxy.
 From what I can tell though, this never actually occurs.

ES5 section 8.12.3 step 8  (the steps start at 8 instead of 1) calls
[[GetProperty]] on the receiver, causing a [[GetProperty]] (not
[[Get]]) call to propogate up the prototype chain, meaning the proxy's
"getPropertyDescriptor" (not "get") trap is called.

ES5 section 8.12.5 step 4 also calls [[GetProperty]] on the receiver,
causing a [[GetProperty]] (not [[Put]]) call to propogate up the
prototype chain, meaning the proxy's "getPropertyDescriptor" (not
"set") trap is called.

Thanks,
Sean Eagan


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