<html><body style="word-wrap: break-word; -webkit-nbsp-mode: space; -webkit-line-break: after-white-space; "><br><div><div>On Oct 18, 2009, at 1:21 PM, Ron Garret wrote:</div><br class="Apple-interchange-newline"><blockquote type="cite"><div style="word-wrap: break-word; -webkit-nbsp-mode: space; -webkit-line-break: after-white-space; "><br><div><div>On Oct 18, 2009, at 4:14 AM, Taoufik Dachraoui wrote:</div><br class="Apple-interchange-newline"><blockquote type="cite"><div style="word-wrap: break-word; -webkit-nbsp-mode: space; -webkit-line-break: after-white-space; ">Also, I would like to insist on the fact that SETF creates a lexical variable (on behavior at least,<div><div>it is weird for me to say that because for me when I learned Common Lisp I was told that</div><div>there a daynamic and lexical variables).</div></div></div></blockquote><div><br></div><div>Insist all you want, that won't make you right.</div><br><blockquote type="cite"><div style="word-wrap: break-word; -webkit-nbsp-mode: space; -webkit-line-break: after-white-space; "><div><div>The following example shows that SETF creates a lexical variable (because f always returns</div><div>the value of x as defined by SETF)</div></div></div></blockquote><div><br></div><div>No, it doesn't:</div><div><br></div><div><div>? (setf x 1)</div><div>1</div><div>? (defun f () (+ x 1))</div><div>;Compiler warnings :</div><div>; In F: Undeclared free variable X</div><div>F</div><div>? (let ((x pi)) (declare (special x)) (f))</div><div>4.141592653589793D0</div><div>? x</div><div>1</div><div>? </div></div><br></div></div></blockquote>This shows that x is really special, it behaves as lexical unless you declare it special</div><div><br></div><div>According to the specs, special specifies that the variable x is dynamic and that x</div><div>refers to the current dynamic binding. But recall before the special declaration x was not </div><div>dynamic. As the example shows, x is a lexical variable.</div><div><br></div><div><br></div><div><blockquote type="cite"><div style="word-wrap: break-word; -webkit-nbsp-mode: space; -webkit-line-break: after-white-space; "><div><blockquote type="cite"><div style="word-wrap: break-word; -webkit-nbsp-mode: space; -webkit-line-break: after-white-space; "><div><div><br></div><div><div>If you do not agree please explain in more details so I learn and understand something new.</div><div><font class="Apple-style-span" color="#000000"><font class="Apple-style-span" color="#144FAE"><br></font></font></div></div></div></div></blockquote><br></div><div>See:</div><div><br></div><div><a href="http://www.flownet.com/ron/specials.pdf">http://www.flownet.com/ron/specials.pdf</a></div><div><br></div><div>rg</div><div><br></div><br></div></blockquote></div><br><div>Taoufik</div></body></html>