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Why does ConcurrentHashMap prevent null keys and values?
...oncurrentMaps
(ConcurrentHashMaps, ConcurrentSkipListMaps) is that ambiguities that
may be just barely tolerable in non-concurrent maps can't be
accommodated. The main one is that if map.get(key) returns null, you
can't detect whether the key explicitly maps to null vs the key isn't
mapped...
How to check if an object is a list or tuple (but not string)?
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edited Apr 16 '18 at 14:21
sorin
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HTML5 check if audio is playing?
...lem) { return !audelem.paused; }
The Audio tag has a paused property. If it is not paused, then it's playing.
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Is std::unique_ptr required to know the full definition of T?
...t templates in the C++ standard library require that they be instantiated with complete types. However shared_ptr and unique_ptr are partial exceptions. Some, but not all of their members can be instantiated with incomplete types. The motivation for this is to support idioms such as pimpl using smar...
How to vertically center divs? [duplicate]
... modern browsers is to use flexbox:
#Login {
display: flex;
align-items: center;
}
Some browsers will need vendor prefixes. For older browsers without flexbox support (e.g. IE 9 and lower), you'll need to implement a fallback solution using one of the older methods.
Recommended Reading
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Vagrant's port forwarding not working [closed]
... of just more comments.
First thing: try curl 'http://localhost:80' from within the VM. If that doesn't work, then it's definitely not the port forwarding.
Next: try curl -v 'http://localhost:4567/' from your host machine. Curl might give you a better error message than Safari.
I'd check that t...
How do I call one constructor from another in Java?
Is it possible to call a constructor from another (within the same class, not from a subclass)? If yes how? And what could be the best way to call another constructor (if there are several ways to do it)?
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How do I redirect output to a variable in shell? [duplicate]
...
This captures the output of a command, but it does not use a redirect. If you actually need to use a redirect because of a more complex need, See my answer. Google brought you here, right? Why go somewhere else to find the answer you searched for?
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What is Python used for? [closed]
What is Python used for and what is it designed for?
2 Answers
2
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How to get temporary folder for current user
...pecified by the USERPROFILE environment variable.
The Windows directory.
It's not entirely clear to me whether "The Windows directory" means the temp directory under windows or the windows directory itself. Dumping temp files in the windows directory itself sounds like an undesirable case, but who...