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Is it safe to delete a void pointer?

... It depends on "safe." It will usually work because information is stored along with the pointer about the allocation itself, so the deallocator can return it to the right place. In this sense it is "safe" as long as your allocator uses internal boundary tag...
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Hidden Features of Java

...en I first discovered it, never heard of it before. ThreadLocals are typically not so widely known as a way to store per-thread state. Since JDK 1.5 Java has had extremely well implemented and robust concurrency tools beyond just locks, they live in java.util.concurrent and a specifically interest...
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Getting the index of the returned max or min item using max()/min() on a list

... values = [3,6,1,5], and need the index of the smallest element, i.e. index_min = 2 in this case. Avoid the solution with itemgetter() presented in the other answers, and use instead index_min = min(range(len(values)), key=values.__getitem__) because it doesn't require to import operator nor to ...
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Finding the type of an object in C++

... dynamic_cast should do the trick TYPE& dynamic_cast<TYPE&> (object); TYPE* dynamic_cast<TYPE*> (object); The dynamic_cast keyword casts a datum from one pointer or reference type to another, performing a runtime...
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appending array to FormData and send via AJAX

... add all type inputs to FormData const formData = new FormData(); for (let key in form) { Array.isArray(form[key]) ? form[key].forEach(value => formData.append(key + '[]', value)) : formData.append(key, for...
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Difference between Java Enumeration and Iterator

...n Enumeration: Iterators differ from enumerations in two ways: Iterators allow the caller to remove elements from the underlying collection during the iteration with well-defined semantics. Method names have been improved. The bottom line is, both Enumeration and Iterator will give successive el...
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How to set auto increment primary key in PostgreSQL?

...hould always be using a primary key on your table because postgresql internally uses hash table structures to increase the speed of inserts, deletes, updates and selects. If a primary key column (which is forced unique and non-null) is available, it can be depended on to provide a unique seed for t...
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What's the difference between Task.Start/Wait and Async/Await?

...ot. How would you like it if waiting for a Task that takes 10 ms would actually execute a 10 hour-long Task on your thread, thus blocking you for the whole 10 hours? – svick Apr 20 '13 at 11:10 ...
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Disable developer mode extensions pop up in Chrome

... to chrome://extensions, check Developer mode and click Pack extension Install the extension by dragging and dropping the .crx file into the chrome://extensions page. You'll get an "Unsupported extensions disabled" popup if you try restarting Chrome at this point. Then for Windows 7 or Windows 8:...
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How do I format a date with Dart?

... You can use the intl package (installer) to format dates. For en_US formats, it's quite simple: import 'package:intl/intl.dart'; main() { final DateTime now = DateTime.now(); final DateFormat formatter = DateFormat('yyyy-MM-dd'); final String formatted...