What is 'p' in this example? On Wednesday, October 17, 2012, Sam Tobin-Hochstadt wrote: <blockquote class="gmail_quote" style="margin:0 0 0 .8ex;border-left:1px #ccc solid;padding-left:1ex">On Tue, Oct 16, 2012 at 7:55 PM, Stephen Bloch <<a href="javascript:;" onclick="_e(event, 'cvml', 'bloch@adelphi.edu')">bloch@adelphi.edu</a>> wrote: >>> Another data point: If "define/match" expands to a "define" of a procedure >>> that dispatches to a set of implementations based on a pattern-match of >>> actual arguments... then the name is exactly what I'd expect for such a >>> feature in a Scheme dialect. >> >> That is, in fact, exactly what it does. > > Cool! My students have been writing code that way for years, and I've been telling them "There are languages in which that would work, but Scheme isn't one of them." > > (define (swap (make-posn x y)) > (make-posn y x)) The syntax looks like: (define/match (swap p) [(posn x y) (posn y x)]) -- sam th <a href="javascript:;" onclick="_e(event, 'cvml', 'samth@ccs.neu.edu')">samth@ccs.neu.edu</a> _________________________ Racket Developers list: <a href="http://lists.racket-lang.org/dev" target="_blank">http://lists.racket-lang.org/dev</a> </blockquote>