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How to write an async method with out parameter?

... @orad I especially like this: private async Task<(bool success, Job job, string message)> TryGetJobAsync(...) – J. Andrew Laughlin Oct 26 '18 at 15:26 ...
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AngularJS : How to watch service variables?

... $watch. In the service: factory('aService', function() { var observerCallbacks = []; //register an observer this.registerObserverCallback = function(callback){ observerCallbacks.push(callback); }; //call this when you know 'foo' has been changed var notifyObservers = function(){...
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Remove the last line from a file in Bash

...e, while $ means "the last line in the file". When specifying a location (called "range" in sed lingo) before a command, that command is only applied to the specified location. So, this command explicitly says "in the range of the last line in a file, delete it". Quite slick and straight to the poin...
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Building big, immutable objects without using constructors having long parameter lists

...of course completely wrong. The trick is that only the build() method actually creates a Foo (hence you Foo can be immutable). FooFactory.create(), whereXXX(..) and withXXX(..) all create "something else". That something else may be a FooFactory, here's one way to do it.... You FooFactory would ...
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How update the _id of one MongoDB Document?

I want update an _id field of one document. I know it's not a really good pratice. But with some technical reason, I need update it. If I try to update it I get: ...
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Calling clojure from java

Most of the top google hits for "calling clojure from java" are outdated and recommend using clojure.lang.RT to compile the source code. Could you help with a clear explanation of how to call Clojure from Java assuming you have already built a jar from the Clojure project and included it in the cl...
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Inheriting class methods from modules / mixins in Ruby

...ors of the class. You can look at the ancestors of any class or module by calling its ancestors method: module M def foo; "foo"; end end class C include M def bar; "bar"; end end C.ancestors #=> [C, M, Object, Kernel, BasicObject] # ^ look, it's right here! When you call a metho...
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Why does the Scala compiler disallow overloaded methods with default arguments?

... such method overloadings could become ambiguous, why does the compiler disallow code which is neither ambiguous at compile time nor at run time? ...
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What does = +_ mean in JavaScript

...s to a number. _ is only a variable name (not an operator), it could be a, foo etc. Example: +"1" cast "1" to pure number 1. var _ = "1"; var r = +_; r is now 1, not "1". Moreover, according to the MDN page on Arithmetic Operators: The unary plus operator precedes its operand and evalua...
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How to use if - else structure in a batch file?

...stion about if - else structure in a batch file. Each command runs individually, but I couldn't use "if - else" blocks safely so these parts of my programme doesn't work. How can I do make these parts run? Thank you. ...