Gödel's Incompleteness Theorem in Bash

Re:Gödel's Incompleteness Theorem in Bash by amluto on Thursday February 24, 2022 @11:29PM (#30463731)

But this is bash, which runs on Unixy systems, which have exec. behave_differently is trivial:

    echo foo
    exec “$@“

This little hack will carry over to some, but possibly not all [0], models of computation. Fixing this would involve cleaning up some definitions in the proof.

[0] Specifically, it does carry over to any model of a program that outputs a stream of symbols one at a time. A single-tape Turing machine that computes a function doesn’t work like that.

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Re:Gödel's Incompleteness Theorem in Bash by assbuttbuttass on Friday February 25, 2022 @12:30AM (#30464016)

What if the program you're running outputs "foo" in an infinite loop?

Then I think the above behave_differently would actually behave the same

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Re:Gödel's Incompleteness Theorem in Bash by KerrickStaley on Friday February 25, 2022 @12:31AM (#30464023)

That does not work. Your example does not change the behavior of the following program:

    echo foo
    exec $0

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Re:Gödel's Incompleteness Theorem in Bash by dskloet on Friday February 25, 2022 @01:29AM (#30464261)

Your program is very close to the above commenter's program. You could have picked the identical program which is exactly what the proof does.

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