https://ask.clojure.org/index.php/tag/knuth https://ask.clojure.org/index.php/10547/is-it-possible-to-implement-label-goto-mechanism-in-clojure <p>Apparently the JVM has a <code>label/goto</code> mechanism. Would it be possible to add such a capability to the Clojure language?</p> <p>I suppose there are two questions which could be addressed 100% independently. <br> 1. whether it is theoretically possible. i.e., to the JVM instructions really permit such a Clojure primitive at all. Perhaps I'm mistaken, and it is really not possible.<br> 2. whether the core Clojure maintainers can be convinced of the merits of the request.</p> <p>In general <code>goto</code> is useful in machine generated code, not so much in human written code.</p> <p>I have at least three use cases where I'd like to have such a mechanism.</p> <ol> <li>serialization of deterministic finite automata</li> <li>serialization of discrimination nets</li> <li>translation of Knuth style algorithms into Clojure from Art of Computer Programming.</li> </ol> <p>I know that lots of people might respond with philosophical arguments about why you shouldn't use goto. I hope to avoid such a discussion here.</p> <p>One possibility which seems reasonable to me would be a Clojure primitive similar to the <a rel="nofollow" href="http://www.lispworks.com/documentation/HyperSpec/Body/m_prog_.htm">Common Lisp prog</a> although the ability to bind variables is not really necessary, as it could easily be implemented by the user by using <code>let</code> with some macrology.</p> Compiler https://ask.clojure.org/index.php/10547/is-it-possible-to-implement-label-goto-mechanism-in-clojure Fri, 30 Apr 2021 08:49:38 +0000