[racket-dev] Typed Racket support for Ephemerons

From: Pierpaolo Bernardi (olopierpa at gmail.com)
Date: Wed Apr 27 05:14:48 EDT 2011

BTW, I think there are a couple of typos in:

"15.2 Ephemerons
An ephemeron [Hayes97] is a generalization of a weak box (see Weak
Boxes). Instead of just containing one value, an e___m___phemeron
holds two values: one that is considered the value of the ephemeron
and another that is the ephemeron’s key. Like the value in a weak box,
the value in ___and___ ephemeron may be replaced by #f, but when the
key is no longer reachable (except possibly via weak references)
instead of when the value is no longer reachable."


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