<HTML><BODY style="word-wrap: break-word; -khtml-nbsp-mode: space; -khtml-line-break: after-white-space; "><BR><DIV><DIV>On Dec 17, 2006, at 10:46 AM, Eli Barzilay wrote:</DIV><BR class="Apple-interchange-newline"><BLOCKQUOTE type="cite"><P style="margin: 0.0px 0.0px 0.0px 0.0px"><FONT face="Helvetica" size="3" style="font: 12.0px Helvetica">ng by default, with some sane treatment</FONT></P> <P style="margin: 0.0px 0.0px 0.0px 0.0px"><FONT face="Helvetica" size="3" style="font: 12.0px Helvetica">of some features like `begin'.<SPAN class="Apple-converted-space"> </SPAN>I didn't even think of the effects of</FONT></P> <P style="margin: 0.0px 0.0px 0.0px 0.0px"><FONT face="Helvetica" size="3" style="font: 12.0px Helvetica">using continuations in the lazy language...)</FONT></P> </BLOCKQUOTE><BR></DIV><DIV><SPAN class="Apple-style-span">That's why I used the word "whimsical". By way of background, I was just thinking about how you could even <I>define</I> continuations without using some sort of environment based evaluation scheme. I know SICP re-implements force and delay in the section on lazy evaluation, but couldn't you write an interpreter that doesn't use environments at all, but just does normal order reduction? I would think so, but what, then, could call/cc possibly mean? I imagine some kind of combinator vaguely analogous to Y, but I'm not quite sure how it would work -- or whether this is all just nonsense.</SPAN></DIV><BR><DIV> <SPAN class="Apple-style-span" style="border-collapse: separate; border-spacing: 0px 0px; color: rgb(0, 0, 0); font-family: Helvetica; font-size: 12px; font-style: normal; font-variant: normal; font-weight: normal; letter-spacing: normal; line-height: normal; text-align: auto; -khtml-text-decorations-in-effect: none; text-indent: 0px; -apple-text-size-adjust: auto; text-transform: none; orphans: 2; white-space: normal; widows: 2; word-spacing: 0px; "><SPAN class="Apple-style-span" style="border-collapse: separate; border-spacing: 0px 0px; color: rgb(0, 0, 0); font-family: Helvetica; font-size: 12px; font-style: normal; font-variant: normal; font-weight: normal; letter-spacing: normal; line-height: normal; text-align: auto; -khtml-text-decorations-in-effect: none; text-indent: 0px; -apple-text-size-adjust: auto; text-transform: none; orphans: 2; white-space: normal; widows: 2; word-spacing: 0px; "><DIV>Gregory Woodhouse</DIV><DIV><A href="mailto:gregory.woodhouse@sbcglobal.net">gregory.woodhouse@sbcglobal.net</A></DIV><DIV><BR class="khtml-block-placeholder"></DIV>"If everything seems under control,<BR class="Apple-interchange-newline"></SPAN><DIV>you're just not going fast enough."</DIV><DIV>-- Mario Andretti</DIV><BR class="Apple-interchange-newline"></SPAN> </DIV><BR></BODY></HTML>