Joe Gilray wrote:
Thanks for sharing your code.
It beats staring blankly at a poorly written PE solution! And when the counter tells you you'll have a result in a week, it's probably time to rethink!
Quick, newby question: why do you use "and" instead of "begin" in your progress function? I've seen others do this as well (of course, Eli's "(and...)" idiom above is a whole different animal... and very cool.
The code was factored out from a #:when clause in my loops, which would read: (for/XXX ([i 1000] #:when (or (> (modulo i 5) 0) [the print bit]) [j 1000] [k 1000] [l 1000]) ...) [the print bit] started life (naively) as: (printf "~a|" i) (flush-output) Unfortunately, the (> ...) clause would fail on i=0,5,... causing the printf to call, which returns void, a true value, so the "or" would succeed without getting to the flush-output. So, as you say, [the print bit] needed bracketing off. A "begin" would have done. But the issue I had was with boolean logic operators so I looked to them for a solution... "and" does the trick. Re Style: looking back on it, my issue was with functions returning void, which I find hard to make an opinion of one way or another whether it should be true, false, or "don't use this in a boolean". (Yes I know only #f is false and all that...). "Begin" would keep me out of that philosophical quandary, and therefore be the style I would prefer, if I had a mind about me! "when" might have been even more appropriate, since it takes a boolean condition and then arbitrary forms -- but I didn't really want to see: #:when (when (> ...) print flush) It's just odd. Hope that hasn't exposed you too much to the darker corners of my thinking, but you did ask! Tim -- Tim Brown <tim.br...@cityc.co.uk> | City Computing Limited | T: +44 20 8770 2110 | City House, Sutton Park Road | F: +44 20 8770 2130 | Sutton, Surrey, SM1 2AE, GB | -----------------------------------------------------------------------| BEAUTY: What's in your eye when you have a bee in your hand | -----------------------------------------------------------------------' City Computing Limited registered in London No. 1767817. Registered Office: City House, Sutton Park Road, Sutton, Surrey, SM1 2AE VAT number 372 8290 34. ____________________ Racket Users list: http://lists.racket-lang.org/users
