In CustomCollationOrder the discussion turned to ways to allow "external" code snippets in a more secure or controllable way. An alternative was a custom expression evaluator library, but since an interpreter typically already has an expression evaluator, it seems like unnecessary duplication of parts. A more powerful EVAL would could facilitate TableOrientedProgramming and other "external code" usage, such as expressions entered by power-users who we otherwise don't want touching the application source code.
An expression evaluator could have an allow and/or deny of the following:
Variable scope:
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