But that does hide the intent of the case-lambda usage, which is captured in the original. <div class="gmail_quote">On Mon, Oct 25, 2010 at 8:21 AM, Sam Tobin-Hochstadt <<a href="mailto:samth@ccs.neu.edu">samth@ccs.neu.edu</a>> wrote: <blockquote class="gmail_quote" style="border-left: 1px solid rgb(204, 204, 204); margin: 0pt 0pt 0pt 0.8ex; padding-left: 1ex;">On Mon, Oct 25, 2010 at 10:06 AM, Doug Williams <div class="im"><<a href="mailto:m.douglas.williams@gmail.com">m.douglas.williams@gmail.com</a>> wrote: > </div><div class="im">> (case-> (->r ((r random-source?) > (a real?) > (b (>/c a))) > real?) > (->r ((a real?) > (b (>/c a))) > real?))) > > I'm not sure that one can be easily rewritten in the current contract > system. [I think I would have to move the b > a constraint into the code > itself in the current contract system. Or, change the argument order and > break backward compatibility.] </div>This can be written as a dependent contract, but with worse error messages. (->i ([r/a (or/c random-source? real?)] [a/b real?]) ([b/opt (r/a a/b) (if (random-source? r/a) (>/c a/b) none/c)]) [result real?]) -- sam th <a href="mailto:samth@ccs.neu.edu">samth@ccs.neu.edu</a> </blockquote></div>