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How to call base.base.method()?

...Derived { public override void Say() { Console.WriteLine("Called from Special Derived."); var ptr = typeof(Base).GetMethod("Say").MethodHandle.GetFunctionPointer(); var baseSay = (Action)Activator.CreateInstance(typeof(Action), this, ptr); baseSay(...
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Difference between getDefaultSharedPreferences and getSharedPreferences

...es a default preference-file name. This default is set per application, so all activities in the same app context can access it easily as in the following example: SharedPreferences spref = PreferenceManager.getDefaultSharedPreferences(this); if (spref.contains("email")) { String sEmailAdd...
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How to install a specific version of a ruby gem?

Using the command-line gem tool, how can I install a specific version of a gem? 6 Answers ...
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Is there a way to use SVG as content in a pseudo element :before or :after

... <div class="author_">Lord Byron</div> .author_ { font-family: 'Playfair Display', serif; font-size: 1.25em; font-weight: 700;letter-spacing: 0.25em; font-style: italic; position:relative; margin-top: -0.5em; color: bla...
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How to filter object array based on attributes?

...art of the new ECMAScript 5th Edition standard, and can be found on almost all modern browsers. For IE, you can include the following method for compatibility: if (!Array.prototype.filter) { Array.prototype.filter = function(fun /*, thisp*/) { var len = this.length >>> 0; if (ty...
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Is there a JavaScript / jQuery DOM change listener?

Essentially I want to have a script execute when the contents of a DIV change. Since the scripts are separate (content script in the Chrome extension & webpage script), I need a way simply observe changes in DOM state. I could set up polling but that seems sloppy. ...
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Difference between object and class in Scala

...ompanion object of class C; note that the companion object is not automatically an instance of C. Also see Scala documentation for object and class. object as host of static members Most often, you need an object to hold methods and values/variables that shall be available without having to firs...
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Correct way to use get_or_create?

...f the fields have to be included in defaults. In case CREATE event occurs, all the fields are taken into consideration. It looks like you need to be returning into a tuple, instead of a single variable, do like this: customer.source,created = Source.objects.get_or_create(name="Website") ...
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is not JSON serializable

...fe tage. stackoverflow.com/a/57939897/4157431 – Rami Alloush Sep 14 '19 at 23:01 add a comment  |  ...
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How do I cast a variable in Scala?

... The preferred technique is to use pattern matching. This allows you to gracefully handle the case that the value in question is not of the given type: g match { case g2: Graphics2D => g2 case _ => throw new ClassCastException } This block replicates the semantics of th...