After browsing your post it seems that although the implementation tools are different the method is similar to the alternative version in the Rosetta Code site (http://rosettacode.org/wiki/Y_combinator#J ). This is not surprising; the general pattern for indirect recursion is to be able represent code (for example, in a gerund, string, number, etc.) and invoke it (for example, using evoke, apply, do, etc.) and when the code refers to this process itself then recursion is a possibility. Quines in one form of another are just a step away from recursion; see, for example, http://www.jsoftware.com/pipermail/programming/2012-April/027819.html .
I do not think I implemented a fixed point combinator either and I doubt it can really be done directly in J because verbs cannot take directly verbs as arguments, and adverbs or conjunctions cannot take directly adverbs or conjunctions (at least not anymore in the current standard implementation of J). Nevertheless, indirect recursion can be implemented neatly as we found out and others before us. On Wed, Jun 13, 2012 at 11:21 AM, Raul Miller <rauldmil...@gmail.com> wrote: > On Tue, Jun 12, 2012 at 8:10 PM, I wrote: >> I believe Jose Quintana has already posted similar material, using >> apply. He might have even posted an implementation exactly like what >> I am posting here. But I am not sure how to find that. > > Here is at least one of the articles I was looking for. > > http://www.jsoftware.com/pipermail/programming/2009-August/016165.html > > Ironically, he points at the same article I pointed at. > > -- > Raul > ---------------------------------------------------------------------- > For information about J forums see http://www.jsoftware.com/forums.htm ---------------------------------------------------------------------- For information about J forums see http://www.jsoftware.com/forums.htm
