<html><head></head><body style="word-wrap: break-word; -webkit-nbsp-mode: space; -webkit-line-break: after-white-space; ">But inverting these functions *is* possible. It's just very, very hard.<div><br></div><div>rg</div><div><br><div><div>On Feb 13, 2010, at 10:55 AM, Taoufik Dachraoui wrote:</div><br class="Apple-interchange-newline"><blockquote type="cite">Hi Ron,<div><br></div><div>I am aware that not all functions have inverses, that is why I said "if possible"</div><div><br></div><div>Kind regards</div><div>Taoufik</div><div><br><br><div class="gmail_quote">On Sat, Feb 13, 2010 at 6:31 PM, Ron Garret <span dir="ltr"><<a href="mailto:ron@flownet.com">ron@flownet.com</a>></span> wrote:<br>
<blockquote class="gmail_quote" style="margin:0 0 0 .8ex;border-left:1px #ccc solid;padding-left:1ex;"><div style="word-wrap:break-word"><br><div><div class="im"><div>On Feb 13, 2010, at 4:20 AM, Taoufik Dachraoui wrote:</div>
<br></div><div class="im"><blockquote type="cite"><div><br></div><div>Does someone know if there is any work done to generate an inverse of any given lisp function (if possible).</div></blockquote></div></div><br><div class="im">
<div>*Any* given function? That would be quite the trick. If you can figure out how to invert, say, AES-ENCRYPT do let us know. Or DELETE-FILE. Inverting multiplication would be pretty cool too. Here's a test case for you:</div>
<div><br></div><div>(funcall (invert #'*) <span style="color:rgb(0, 0, 255);font-family:arial, verdana, 'ms sans serif';font-size:12px;line-height:17px">412023436986659543855531365332575948179811699844327982845455626433876445565248426198098870423161841879261420247188869492560931776375033421130982397485150944909106910269861031862704114880866970564902903653658867433731720813104105190864254793282601391257624033946373269391)</span></div>
<div><br></div><div>rg</div><div><br></div></div></div></blockquote></div><br></div>
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