Interesting idea, though any properties that change/morph would need deterministic rules which the LLM could likely easily replicate. Unless I'm missing something.
Programming state gets way more complicated, but code is generally written to help people understand it greatly simplifying the process. Feed in “cursed” code leveraging obscure language features in creative ways and LLM’s and most people fail.
You're right that it's worth considering in the same way as the letter counting tricks, since coding agents can get around that in the same way. But I would say the letter counting has the advantage that it at least is easy for humans.
I am just as interested in making the language hard for LLMs as for LLMs+coding agents though.
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