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Does setting Java objects to null do anything anymore?

... object chain A->B->C, then once A is not reachable, A, B and C will all be eligible for garbage collection (assuming nothing else is referring to either B or C). There's no need, and never has been any need, to explicitly set references A->B or B->C to null, for example. Apart from tha...
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Why Func instead of Predicate?

... Well, actually you have to place that in the context of the guideline, which is about writing a LINQ provider. So yeah, for LINQ operators, the guideline is to use Func<> and Expression<> as parameters for the extension met...
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How do I capture SIGINT in Python?

...f KeyboardInterruptException is implemented as a SIGINT handler or if it really only catches Ctrl+C presses, but either way, using a signal handler makes your intent explicit (at least, if your intent is the same as OP's). More importantly though, with a signal you don't have to wrap try-catches ar...
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What is the difference between old style and new style classes in Python?

...(x) is always <type 'instance'>. This reflects the fact that all old-style instances, independently of their class, are implemented with a single built-in type, called instance. New-style classes were introduced in Python 2.2 to unify the concepts of class and type. A new-s...
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HEAD and ORIG_HEAD in Git

..., and it is a commit on top of which "git commit" would make a new one. Usually HEAD is symbolic reference to some other named branch; this branch is currently checked out branch, or current branch. HEAD can also point directly to a commit; this state is called "detached HEAD", and can be understood...
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Is it possible to forward-declare a function in Python?

...rwards is impossible, what about defining it in some other module? Technically you still define it first, but it's clean. You could create a recursion like the following: def foo(): bar() def bar(): foo() Python's functions are anonymous just like values are anonymous, yet they can be ...
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How do I expire a PHP session after 30 minutes?

...ms with filesystems where atime tracking is not available. So it additionally might occur that a session data file is deleted while the session itself is still considered as valid because the session data was not updated recently. And second: session.cookie_lifetime session.cookie_lifetime ...
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How can I provide multiple conditions for data trigger in WPF?

...D are false, and set the default to true. – WeSam Abdallah Oct 28 '14 at 15:47 3 ...
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Database Structure for Tree Data Structure

... using the employee ID to link an employee to their supervisor. This is usually a sub-optimal approach. An approach that often works better is to model the org structure separate from employees themselves, and maintain the employee as an attribute of the structure. This way, when an employee leaves ...
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File Upload ASP.NET MVC 3.0

...maxRequestLength="x" /> in your web.config, where x is the number of KB allowed for upload. – rsbarro May 22 '11 at 20:33 86 ...