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in reply to Re^3: Worst blog post ever on teaching programming
in thread Problematic post on teaching programming

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. --
Ytrew

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Re^5: Worst blog post ever on teaching programming
by bigmacbear (Monk) on Apr 11, 2006 at 00:43 UTC
    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.

    A thought experiment? You mean like Schrödinger's half-dead cat in a box?

Re^5: Worst blog post ever on teaching programming
by jdporter (Chancellor) on Apr 28, 2006 at 14:01 UTC
    Please explain where you got the infinitely long tape...

    You are mistaken. There is no requirement in the definition of Turing machine that the tape be actually infinite in size. It merely needs to be unbounded. As long as an implementation, in its execution, doesn't exceed the limits of its "tape", there's no reason it can't be a Turing machine.

    We're building the house of the future together.