<META HTTP-EQUIV="Content-Type" CONTENT="text/html; charset=utf-8"> <!DOCTYPE HTML PUBLIC "-//W3C//DTD HTML 3.2//EN"> <HTML> <HEAD> <META NAME="Generator" CONTENT="MS Exchange Server version 6.0.6249.1"> <TITLE>[plt-scheme] Dead lock using map-stream?</TITLE> </HEAD> <BODY dir=ltr> <DIV>First of all, what good would that thing do?</DIV> <DIV>map-stream calls proc for each element of the stream, or in other words, calls (+ 0), (+ 1), etc. and streams them.</DIV> <DIV>Second, does (enumerate-interval 0 10) work?</DIV> <DIV> </DIV> <BLOCKQUOTE dir=ltr style="MARGIN-RIGHT: 0px"> <DIV>-----Original Message----- From: Gurpreet S. Saini [mailto:gsaini@u.washington.edu] Sent: א 23/11/2003 05:08 To: plt-scheme@list.cs.brown.edu Cc: Subject: [plt-scheme] Dead lock using map-stream? </DIV>   For list-related administrative tasks:   <A href="http://list.cs.brown.edu/mailman/listinfo/plt-scheme">http://list.cs.brown.edu/mailman/listinfo/plt-scheme</A> [Note that both of definitions come from chapter 3 of the first edition of SICP] Consider 1. the following defintions: (define the-empty-stream '()) (define (enumerate-interval low high)         (if (> low high)             the-empty-stream             (cons-stream low                         (enumerate-interval (+ low 1) high)))) (define (map-stream proc stream)     (if (empty-stream? stream)          the-empty-stream          (cons-stream (proc (head stream))                       (map-stream proc (tail stream))))) 2. And the following call: (map-stream + (enumerate-interval 0 10)) Right now this call is stalled. It looks to me like this is supposed to happen. This is because both enumerate-interval and map-stream's call to tail is in a cons-stream. thanks --Gurp </BLOCKQUOTE> </BODY> </HTML>