That's too bad (I mean, its good for performance, but unfortunate one of the use cases doesn't exist). However, the treap functions may still be of general use. Let me know if there is any interest. They are documented and tested. They fill a gap between alists (persistent, linear lookup) and hash tables (ephemeral, constant lookup) by being persistent while providing average case logarithmic lookup.
> now. I intend to use these functions to make lexically-scoped variableAFAIK it's O(1) currently (for byte-compiled code only, but performance
> lookup average case O(log(n)) instead of the current O(n).
of non-byte-compiled code should be of no importance).
Stefan