I think the synchronous inspection API we have currently is clunky. My ideal one would look like promise.inspect() (or inspectState, or snapshot, or stateSnapshot, ...), which returns a "snapshot" object that is one of:

• { state = "pending" }
• { state = "fulfilled", value }
• { state = "rejected", reason }

The advantage of this over promise.state, promise.value, and promise.reason are:

• In ES3, properties on the promise have to be mutable, which is confusing.
• Even in ES5, if we were to make those getters, I think it's less-clear that they are a read-only API than a snapshot-returning function.
• Reduced surface area.
• Usefulness for Q.allSettled (see Q.allSettled #257).