Path: news.eternal-september.org!eternal-september.org!.POSTED!not-for-mail From: Keith Thompson Newsgroups: comp.theory Subject: Re: Unpartial Halt Deciders Date: Fri, 18 Apr 2025 12:25:36 -0700 Organization: None to speak of Lines: 25 Message-ID: <87zfgdnufj.fsf@nosuchdomain.example.com> References: MIME-Version: 1.0 Content-Type: text/plain Injection-Date: Fri, 18 Apr 2025 21:25:38 +0200 (CEST) Injection-Info: dont-email.me; posting-host="296572f88f5dccb657107911794e9333"; logging-data="3810687"; mail-complaints-to="abuse@eternal-september.org"; posting-account="U2FsdGVkX1/zYNHqtx1V3nM3GzqOcoRk" User-Agent: Gnus/5.13 (Gnus v5.13) Cancel-Lock: sha1:hZR1AZ2PStz+uVs9jIILQPLTOGE= sha1:LIrlVMTDoobFCWXo9wPx60fv2eQ= Mr Flibble writes: > I, aka Mr Flibble, have created a new computer science term, the > "Unpartial Halt Decider". It is a Halt Decider over the domain of all > program-input pairs excluding pathological input (a manifestation of the > self referencial category error). [...] Do you have a rigorous definition of "pathological input"? Is there an algorithm to determine whether a given input is "pathological" or not? I could define an is_prime() function like this: bool is_prime(int n) { return n >= 3 && n % 2 == 1; // returns true for odd numbers >= 3, false for all others } I'll just say that odd numbers that are not prime are pathological input, so I don't have to deal with them. -- Keith Thompson (The_Other_Keith) Keith.S.Thompson+u@gmail.com void Void(void) { Void(); } /* The recursive call of the void */