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Better way to cast object to int

... to signify a Nullable<int>. The "as" operator works like Convert.To____(), but think TryParse() rather than Parse(): it returns null rather than throwing an exception if the conversion fails. Of these, I would prefer (int) if the object really is just a boxed integer. Otherwise use Conver...
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How can I restore the MySQL root user’s full privileges?

...ue the following commands in the mysql client: UPDATE mysql.user SET Grant_priv='Y', Super_priv='Y' WHERE User='root'; FLUSH PRIVILEGES; After that, you should be able to run GRANT ALL ON *.* TO 'root'@'localhost'; and have it work. ...
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Refresh a page using JavaScript or HTML [duplicate]

...g (ajax) at loading. for example: www.yoursite.com/page/about?getVer=1&__[date] Compare it to the stored versionnumber (stored in cookie or localStorage) if user has visited the page once, otherwise store it directly. If version is not the same as local version, refresh the page using window.loc...
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Gem::LoadError for mysql2 gem, but it's already in Gemfile

...s 4.1.5) try using this version of mysql2: gem 'mysql2', '~> 0.3.18' Apparently mysql2 isn't still compatible with newer version of rails because rails 4.2.4 is pretty new as the time of answering this question by me 8 September 2015 so use the above line in your Gem file and run: bundle ins...
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How to iterate a loop with index and element in Swift

...100, height: 100) button.addTarget(self, action: #selector(iterate(_:)), for: .touchUpInside) view.addSubview(button) } @objc func iterate(_ sender: UIButton) { let tuple = generator.next() print(String(describing: tuple)) } } PlaygroundPage.current.liv...
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What's the difference between eval, exec, and compile?

...n Python is whatever you can have as the value in a variable assignment: a_variable = (anything you can put within these parentheses is an expression) eval returns the value of the given expression, whereas exec ignores the return value from its code, and always returns None (in Python 2 it is a s...
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Programmatically open new pages on Tabs

... You can, in Firefox it works, add the attribute target="_newtab" to the anchor to force the opening of a new tab. <a href="some url" target="_newtab">content of the anchor</a> In javascript you can use window.open('page.html','_newtab'); Said that, I partially ag...
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How efficient is locking an unlocked mutex? What is the cost of a mutex?

...tefultask-testsuite/blob/b69b112e2e91d35b56a39f41809d3e3de2f9e4b8/src/mutex_test.cxx Note that it has a few hardcoded values specific for my box (xrange, yrange and rdtsc overhead), so you probably have to experiment with it before it will work for you. The graph it produces in that state is: T...
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Easiest way to open a download window without navigating away from the page

...for IE6 or not, but this prompts OpenFileDialog in FF and Chrome. var file_path = 'host/path/file.ext'; var a = document.createElement('A'); a.href = file_path; a.download = file_path.substr(file_path.lastIndexOf('/') + 1); document.body.appendChild(a); a.click(); document.body.removeChild(a); ...
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Rails: fields_for with index?

...s there a method (or way to pull off similar functionality) to do a fields_for_with_index ? 9 Answers ...