Ditto what everyone is saying about transactions. That said… ActiveRecord as of Rails 2.1 keeps track of the attribute values of an object. So if you have an attribute total, you will have a total_changed? method and a total_was method that returns the old value. There’s no need to add anything to your model to … Read more
This is a simple question but the answer is surprisingly complex. The short answer is you can do what you’re trying to do with std::bind1st or boost::bind. The longer answer is below. The compiler is correct to suggest you use &CLoggersInfra::RedundencyManagerCallBack. First, if RedundencyManagerCallBack is a member function, the function itself doesn’t belong to any … Read more
Rails 3.1 introduced update_column, which is the same as update_attribute, but without triggering validations or callbacks: http://apidock.com/rails/ActiveRecord/Persistence/update_column
I personally prefer typeof callback === ‘function’ && callback(); The typeof command is dodgy however and should only be used for “undefined” and “function” The problems with the typeof !== undefined is that the user might pass in a value that is defined and not a function
Consider this code: b = Button(admin, text=”as”, command=button(‘hey’)) It does exactly the same as this: result = button(‘hey’) b = button(admin, text=”as”, command=result) Likewise, if you create a binding like this: listbox.bind(“<<ListboxSelect>>”, some_function()) … it’s the same as this: result = some_function() listbox.bind(“<<ListboxSelect>>”, result) The command option takes a reference to a function, which is … Read more
Instead of having static methods and passing around a pointer to the class instance, you could use functionality in the new C++11 standard: std::function and std::bind: #include <functional> class EventHandler { public: void addHandler(std::function<void(int)> callback) { cout << “Handler added…” << endl; // Let’s pretend an event just occured callback(1); } }; The addHandler method … Read more
William Jockusch’s answer solve this problem with easy trick. -(void) viewWillDisappear:(BOOL)animated { if ([self.navigationController.viewControllers indexOfObject:self]==NSNotFound) { // back button was pressed. We know this is true because self is no longer // in the navigation stack. } [super viewWillDisappear:animated]; }
I get this error message and it mentions options.body I had this originally request.post({ url: apiServerBaseUrl + ‘/v1/verify’, body: { email: req.user.email } }); I changed it to this: request.post({ url: apiServerBaseUrl + ‘/v1/verify’, body: JSON.stringify({ email: req.user.email }) }); and it seems to work now without the error message…seems like bug though. I think … Read more
There’s a passReqToCallback option that you can enable, like so: passport.use(new LocalStrategy( {usernameField: ’email’, passReqToCallback: true}, function(req, email, password, done) { // now you can check req.body.foo } )); When, set req becomes the first argument to the verify callback, and you can inspect it as you wish.
If you don’t need anything fancy like delaying the evaluation of the function name or its arguments, you don’t need eval: function x() { echo “Hello world”; } function around() { echo before; $1; echo after; } around x does what you want. You can even pass the function and its arguments this way: function … Read more