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Feature Toggle

$(document).one('feature-a', '#some-id', function() {
  $(document).on('some-event', '#some-ids', handler);
});

//Turn on feature a
$('#a, #b').trigger('feature-a');

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ruby -run -e httpd . -p 3000

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(def x (agent 0))
@x ; 0
(send x inc)
@x ; 1
(send x + 10)
@x ; 11

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(clojure.core.logic/unifier '[(+ ?x 1) (inc ?x)] '[(+ a 1) ?refactored])
;[(+ a 1) (inc a)]

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# http://gitready.com/intermediate/2009/02/06/helpful-command-aliases.html
git config --global alias.rb rebase
git config --global alias.st status
git config --global alias.ci commit
git config --global alias.br branch
git config --global alias.co checkout
git config --global alias.df df
git config --global alias.lg log -p

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public static float distFrom(float lat1, float lng1, float lat2, float lng2) {
    double earthRadius = 3958.75;
    double dLat = Math.toRadians(lat2-lat1);
    double dLng = Math.toRadians(lng2-lng1);
    double a = Math.sin(dLat/2) * Math.sin(dLat/2) +
               Math.cos(Math.toRadians(lat1)) * Math.cos(Math.toRadians(lat2)) *
               Math.sin(dLng/2) * Math.sin(dLng/2);
    double c = 2 * Math.atan2(Math.sqrt(a), Math.sqrt(1-a));
    double dist = earthRadius * c;

yuanmai

;; from http://www.learningclojure.com/2010/09/astonishing-macro-of-narayan-singhal.html
(defmacro def-let
  "like let, but binds the expressions globally."
  [bindings & more]
  (let [let-expr (macroexpand `(let ~bindings))
        names-values (partition 2 (second let-expr))
        defs   (map #(cons 'def %) names-values)]
    (concat (list 'do) defs more)))

;; from http://blog.gaz-jones.com/2012/02/04/debug_let.html

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  (def long-list (into (repeat 10000 0) [9 9 9 9 9]))
  (dotimes [_ 10]
    (time
     (dotimes [_ 1000]
       (sort long-list)
       )))

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ab -n 5000 -c 50 http://localhost:8080/

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[MBProgressHUD showHUDAddedTo:[self.view.window.subviews objectAtIndex:0] animated:YES];
dispatch_async(dispatch_get_global_queue( DISPATCH_QUEUE_PRIORITY_LOW, 0), ^{
    // Do something...
    dispatch_async(dispatch_get_main_queue(), ^{
        [MBProgressHUD hideHUDForView:[self.view.window.subviews objectAtIndex:0]  animated:YES];
    });
});


[MBProgressHUD HUDForView: [UIApplication sharedApplication].keyWindow]