Re^2: Perl is not Dynamically Parseable

[Jeffrey Kegler]

Thanks for the feedback. In response, I've revised the original post in a way that I hope improves it.

An alternative approach would be to simply state the result and that it is a direct and almost trivial consequence of Rice's Theorem. This result is indeed so trivial mathematically that it is unpublishable, but in a math journal, that's how it would be presented. The article would be very short.

Because of the significance of these results, I've labored to present them to readers who are Perl-literate, but not fluent in Theory of Computation. The risk is always that a translation from math-speak will seem sloppy to those who understand it and unconvincing to those who don't.

[ikegami]

Concerning your update:

So therefore, Fallacious Conclusion: We can determine, for arbitrary Perl code, whether any Perl function has a nullary prototype or not.

It's not clear what that means. Are you talking about a function declaration in the source, a function instance produced by a given parser instance, or the function instances produced by every parser instance.

First, let me concede that the Fallacious Conclusion does follow from Observations 1-4.

You can't concede the validity of an argument. You are making an assertion.

And your assertion is false. The conclusion doesn't follow from the premises (anymore?).

Perl's compile phase does have Turing machine power,

You can't use that premise. That's the conclusion of the argument you're trying to verify.