<html><head></head><body style="word-wrap: break-word; -webkit-nbsp-mode: space; -webkit-line-break: after-white-space; ">Thank you for this piece of very good advice! I will change the direction as you suggested, and it is good to know that the problem was not that I had missed something, but that my approach was not feasible.<div><br></div><div><div> <span class="Apple-style-span" style="border-collapse: separate; color: rgb(0, 0, 0); font-family: Helvetica; font-style: normal; font-variant: normal; font-weight: normal; letter-spacing: normal; line-height: normal; orphans: 2; text-align: -webkit-auto; text-indent: 0px; text-transform: none; white-space: normal; widows: 2; word-spacing: 0px; -webkit-border-horizontal-spacing: 0px; -webkit-border-vertical-spacing: 0px; -webkit-text-decorations-in-effect: none; -webkit-text-size-adjust: auto; -webkit-text-stroke-width: 0px; font-size: medium; "><div>Best,</div><div><br></div><div>-Mikko</div></span> </div> <br><div><div>On 12.4.2012, at 21:38, Jay McCarthy wrote:</div><br class="Apple-interchange-newline"><blockquote type="cite"><div>Using Racket predicates like that would be a very bad idea and hard to<br>get working as you've discovered.<br><br>I think the correct approach is to wrap the Racklog program in a<br>Racket program that makes queries of the *log and then asks questions<br>of the user afterwards and repeats the query if necessary.<br><br>I think of *log as a database that exists at an arm's reach from the<br>computation of import and so it shouldn't do too much work and<br>definitely shouldn't do IO.<br><br>Jay<br><br>-- <br>Jay McCarthy <<a href="mailto:jay@cs.byu.edu">jay@cs.byu.edu</a>><br>Assistant Professor / Brigham Young University<br><a href="http://faculty.cs.byu.edu/~jay">http://faculty.cs.byu.edu/~jay</a><br><br>"The glory of God is Intelligence" - D&C 93<br></div></blockquote></div><br></div></body></html>