*In fact, I once implemented a Turing machine in production code because it was the correct and cost-effective solution to the requirements.*
Really? Please explain where you got the infinitely long tape, and how your software made markings on it. If you didn't do that, then you didn't make Turing's machine; and any computing device with an infinite datastore that we can concieve of is computationally equivalent to a Turing machine.

Turing machines are just a theoretical device for discussions of computational equivalence; you can't "implement" one in any sense of the word. You can create a state machine with an associated finite datastore, but we tend to call those devices "computers"; the hardware already does that for us.

There's no sense of the word in which I can find it meaningful to claim one has "implemented" a Turing machine; it's a thought experiment, not a device you can actually build.
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Ytrew

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