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What is the point of the diamond operator () in Java 7?
... that the constructor for a generic type automatically infers its type param>me m>ters from the left-hand side of the assignm>me m>nt if possible. But it didn't, and it must treat raw types and generic types differently for backwards compatibility. That leaves them needing to make a slightly different, but eq...
What are the differences between delegates and events?
... declare an event without a backend delegate instance. In c#, you can implem>me m>nt an event explicitly and use a different backend data structure of your choice.
– Miguel Gamboa
Feb 18 '15 at 11:23
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When should I use Arrow functions in ECMAScript 6?
...row functions are used consistently, everything is guaranteed to use the sam>me m> thisObject as the root. If even a single standard function callback is mixed in with a bunch of arrow functions there's a chance the scope will becom>me m> m>me m>ssed up.
Compactness: Arrow functions are easier to read and write. (...
Position Relative vs Absolute?
...s going to be positioned should be removed from the normal flow of the docum>me m>nt and will be placed in an exact location on the page. It won't affect how the elem>me m>nts before it or after it in the HTML are positioned on the Web page however it will be subject to it's parents' positioning unless you ov...
Check whether a path is valid in Python without creating a file at the path's target
I have a path (including directory and file nam>me m>).
I need to test if the file-nam>me m> is a valid, e.g. if the file-system will allow m>me m> to create a file with such a nam>me m>.
The file-nam>me m> has som>me m> unicode characters in it.
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Why does my JavaScript code receive a “No 'Access-Control-Allow-Origin' header is present on the req
... on. So the browser is blocking it as it usually allows a request in the sam>me m> origin for security reasons. You need to do som>me m>thing different when you want to do a cross-domain request. A tutorial about how to achieve that is Using CORS.
When you are using postman they are not restricted by this po...
When and why are database joins expensive?
I'm doing som>me m> research into databases and I'm looking at som>me m> limitations of relational DBs.
7 Answers
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What's the difference between SoftReference and WeakReference in Java?
...s a
reference that isn't strong enough to
force an object to remain in m>me m>mory.
Weak references allow you to leverage
the garbage collector's ability to
determine reachability for you, so you
don't have to do it yourself. You
create a weak reference like this:
WeakReference weakWidget ...
When and why will a compiler initialise m>me m>mory to 0xCD, 0xDD, etc. on malloc/free/new/delete?
I know that the compiler will som>me m>tim>me m>s initialize m>me m>mory with certain patterns such as 0xCD and 0xDD . What I want to know is when and why this happens.
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Is there a way to cache GitHub credentials for pushing commits?
...:// on GitHub (due to firewall issues), and it asks for a password every tim>me m>.
24 Answers
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