What does HackerNews think of radiation-hardened-quine?
A robust quine program that works even after any one character is deleted.
Binary bitflip resilience is really cool. The radiation-hardened-quine idea (https://codegolf.stackexchange.com/questions/57257/radiation..., https://github.com/mame/radiation-hardened-quine) is cool, but these source-based approaches depend on a perfectly functioning and rather large (Ruby, V8, whole browser) binary stack. A bitflip-protected hex monitor or kernel, on the other hand...
The same author also has a radiation-hardened quine, which still emits the original quine even if you delete any(!) one character before running it: https://github.com/mame/radiation-hardened-quine
But coming back to traditional quines; the most common solution is of the form:
> The following string followed by itself in quotes: "The following string followed by itself in quotes: "
This is by no means the only possible solution: If you view the compiler/interpreter as a function then a quine is the fixpoint of that function.
So, if your "compiler" is `cat`, the shell identity function, then any string is a quine! A fork bomb is also a kind of quine. The quine there is not the code itself, but a process running the code. That process is "interpreted" by the kernel, which dutifully creates an exact copy of the fork-bomb process.
I've never sat down and tried it, but one day I want to write a quine of the form: "Initialize a PRNG with this seed and print the first n bytes". Probably there's a language which lets you get the required code small enough that you could brute-force the correct seed.
https://github.com/mame/quine-relay/blob/master/thumbnail.pn...
That and the radiation-hardened quine:
https://github.com/mame/radiation-hardened-quine
Prior to seeing those, I was kind of dismissive of Ruby, but seeing those totally changed my mindset about code, and my prevailing opinion of execution environments and interpretted languages and scripting in general.
Would be amazing if the method used for implementing it could be generalised somehow.