The following paper was posted to Lambda the Ultimate Weblog yesterday, describing a language construct for introducing implicit, dynamically-scoped parameters into type-safe Haskell. I thought that this might provide some useful information in trying to reconcile Squeak's exception-handling with E's security discipline.
Implicit Parameters: Dynamic Scoping with Static Types http://www.cse.ogi.edu/~jlewis/implicit.ps.gz
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