Mark S. Miller

Proxy as handler for another proxy is indeed an important use case. This is the double lifting technique. We carefully constrained the proxy design so this would work well.

[preserve-proxy-transparency.pdf](https://github.com/tvcutsem/es-lab/files/1511961/preserve-proxy-transparency.pdf) Attached is the slideshow I was preparing in order to present this as a proposal to tc39. It stops at the point where I realized this proposal cannot possibly...

Why must the proxies in a membrane trap on `getPrototypeOf`? Say we have * normal non-exotic wet objects x, y, z, * dry-to-wet proxies xp, yp, zp, emulating x, y,...

@tvcutsem Yes. Well put. One additional part of my thinking: The main use case for proxies, and the use case for which we invented proxies and weakmaps, is membranes. Only...

> If you're telling me that block params can change the bound this of a function object, then I believe there is an object-capability security violation. @erights can you check...

Crucial to this suggestion is that it would apply to `do` expressions as well. Anywhere we might be tempted to use completion value, we should use this instead. The absent...

`instanceof` is definitely a nominal-like test, not a structural-like one. Btw, somewhere I heard the following hilarious observation: Nominal types are about class names. Structural types are about method names.

I like this a lot! Deprecation is somewhat of an issue. Fortunately, most packages only use a `checkFoo` internally, exporting only the `isFoo` and `assertFoo` callers, which would not need...

I like the direction. I'm ok with the choice of `matchesFoo` but the collision you mention does make it awkward. You mention `test`. How about `testFoo`? I think I like...

After more reflection, I really don't like `matchesFoo` because it sounds too specific to patterns and pattern matching. I also no longer like `testFoo` because it sounds like it has...