Path: utzoo!utgpu!jarvis.csri.toronto.edu!mailrus!cs.utexas.edu!uunet!bloom-beacon!spdcc!ima!esegue!compilers-sender From: worley@compass.com (Dale R. Worley) Newsgroups: comp.compilers Subject: Graph reduction, recursion, and the Y combinator Message-ID: <1989Sep26.041357.26728@esegue.segue.boston.ma.us> Date: 26 Sep 89 04:13:57 GMT Sender: compilers-sender@esegue.segue.boston.ma.us Reply-To: worley@compass.com (Dale R. Worley) Organization: Compilers Central Lines: 16 Approved: compilers@esegue.segue.boston.ma.us In most discussions of graph reduction execution of the combinator representation of the lambda calculus, recursive functions are represented by introducing a circularity in the tree that represents the function defintion. In theoretically pure lambda calculus, recursion is expressed using the Y combinator, or some such, which can be represented in terms of the simpler combinators. Has anyone actually done this in graph reduction execution? Has anyone analyzed the optimization which removes the Y and replaces it with the circular edge? Is this a special case of a more general optimization? Dale worley@compass.com -- Send compilers articles to compilers@esegue.segue.boston.ma.us {spdcc | ima | lotus}!esegue. Meta-mail to compilers-request@esegue. Please send responses to the author of the message, not the poster.