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Nullable types and the ternary operator: why is `? 10 : null` forbidden? [duplicate]
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The compiler first tries to evaluate the right-hand expression:
GetBoolValue() ? 10 : null
The 10 is an int literal (not int?) and null is, well, null. There's no implicit conversion between those two hence the error message.
If you change the right-hand expression to ...
What does -> mean in Python function definitions?
...to attach a metadata string to various types of object. This is amazingly handy, so Python 3 extends the feature by allowing you to attach metadata to functions describing their parameters and return values.
There's no preconceived use case, but the PEP suggests several. One very handy one is to al...
Ruby class instance variable vs. class variable
...mmon to that class without having sub-classes automatically also get them (and vice-versa). With class variables, you have the convenience of not having to write self.class from an instance object, and (when desirable) you also get automatic sharing throughout the class hierarchy.
Merging these t...
Is !important bad for performance?
I hate them, it defies the cascading nature of CSS, and if you don't use them with care you end up in a loop of adding more !important .
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In laymans terms, what does 'static' mean in Java? [duplicate]
... beginner to Java I'm still not sure what it means. Anybody fluent in Java and idiot?
6 Answers
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Visual Studio : short cut Key : Duplicate Line
Is there a shortcut for Duplicate Line command in Visual Studio 2008?
30 Answers
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What is the difference between MySQL, MySQLi and PDO? [closed]
What is the difference between MySQL, MySQLi and PDO ?
4 Answers
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When to use AtomicReference in Java?
...e = someFunctionOfOld(cachedValueToUpdate);
boolean success = cache.compareAndSet(cachedValue,cachedValueToUpdate);
Because of the atomic reference semantics, you can do this even if the cache object is shared amongst threads, without using synchronized. In general, you're better off using synchro...
Android: How to turn screen on and off programmatically?
... the traditional sense. It makes the screen as dim as possible. In the standard platform there is a limit to how dim it can be; if your device is actually allowing the screen to turn completely off, then it is some peculiarity of the implementation of that device and not a behavior you can count o...
Xcode debugger doesn't print objects and shows nil, when they aren't
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Ah ok, I created an empty project and can now see all the differences in the Build Settings, the deployment property Strip debug symbols during copy was set to YES.
– Binarian
Nov 11 '13 at 11:32
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