Does 'define' really mean 'make a field'? I thought fields had to be specially designated so that get-field would know about them...<div><br></div><div>Yes, this program errors:</div><div><br></div><div><div> #lang racket</div><div><br></div><div>(define c%</div><div> (class* object% ()</div><div> (field [x 1])</div><div> (define y 2)</div><div> (super-new)))</div><div><br></div><div>(define o (new c%))</div><div><br> </div><div>(field-names o)</div><div>(get-field x o)</div><div>(get-field y o)</div><div><br></div><div>--</div><div><br></div><div>I agree that 'define' is like making a field, but fields are something special too.</div> <div><br></div><div>Jay</div><br><div class="gmail_quote">On Thu, Dec 16, 2010 at 6:51 AM, Robby Findler <span dir="ltr"><<a href="mailto:robby@eecs.northwestern.edu">robby@eecs.northwestern.edu</a>></span> wrote:<br> <blockquote class="gmail_quote" style="margin:0 0 0 .8ex;border-left:1px #ccc solid;padding-left:1ex;">On Thu, Dec 16, 2010 at 12:22 AM, Mark Engelberg<br> <div class="im"><<a href="mailto:mark.engelberg@gmail.com">mark.engelberg@gmail.com</a>> wrote:<br> </div>> OK, it works when the set! occurs after the super-new. I didn't think set!<br> > would work at all in a class definition (as opposed to within a method); I<br> > was thinking of the whole system of defining classes as more of a<br> > declarative DSL that only allowed certain constructs.<br> <br> You've probably already figured this out, but the body of a class is a<br> series of definitions and expressions like at the top-level but<br> 'define' taking on the meaning of 'make a field', and a bunch of new<br> definitions appearing. The new stuff says what the methods are, but<br> everything else is just executed in sequence as if it were in the body<br> of the initializer (if this were in Java, say).<br> <br> hth,<br> <font color="#888888">Robby<br> </font><div><div></div><div class="h5">_________________________________________________<br> For list-related administrative tasks:<br> <a href="http://lists.racket-lang.org/listinfo/dev" target="_blank">http://lists.racket-lang.org/listinfo/dev</a></div></div></blockquote></div><br><br clear="all"><br>-- <br>Jay McCarthy <<a href="mailto:jay@cs.byu.edu" target="_blank">jay@cs.byu.edu</a>><br> Assistant Professor / Brigham Young University<br><a href="http://faculty.cs.byu.edu/~jay" target="_blank">http://faculty.cs.byu.edu/~jay</a><br><br>"The glory of God is Intelligence" - D&C 93<br> </div>