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Thank you. Of course the dates were out of order. The Java library (com.hp.creals) is 1999-2004, paper is from 2005. Unfortunate price of LLM-assisted development. Corrected.

This is different from a CAS. For example, if you ask it to do exp(100)+1-exp(100), it does not rearrange and cancel out the two exp(100)s. Instead, it does exp, addition, and subtraction, all with as many digits as you ask for.

Author here. I could not find a constructive‑reals calculator on iPhone, so I ported the engine Android uses: Hans Boehm's com.hp.creals plus AOSP's UnifiedReal/BoundedRational. Used Opus 4.8 to do the port and Fable 5 for the review.

Fable 5 caught a couple of real concurrency bugs the port introduced while adapting Java's synchronized/AsyncTask to Swift concurrency, including one that was a memory‑safety bug on shared singletons like π, not just a wrong digit. None would have shown up in the unit tests. Writeup has the details.

It's an early iPhone TestFlight beta (link in the post); happy to go deep on either the constructive‑reals side or the AI‑assisted‑dev side.

Looks like it uses seven colors (including bodies of water). Can it be done with fewer colors? The four color theorem does not quite apply, as all bodies of water have to be the same color.

Eskimo bowline is non-exploding, nevertheless I wouldn't use bowline (or eskimo bowline) while rock climbing without somehow securing the working end.

Kalmyk loop (which is exploding variant of eskimo bowline) is probably not secure enough for rock climbing, but better than bowline for other tasks. Less likely to spill and easier to untie.

Kalmyk loop is exploding - pull to untie. Bowline is not.

Bowline requires stopper knots when used on on modern ropes, otherwise it can slip. I've never seen kalmyk loop slip.

Both are simple and can be tied around things.