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Why is my Spring @Autowired field null?
... top of your answer that explains that retrieving the first bean, the root from which you do everything, should be done through the ApplicationContext. Some users (for which I've closed as duplicates) don't understand this.
– Sotirios Delimanolis
Oct 18 '14 at ...
Method call if not null in C#
...
From C# 6 onwards, you can just use:
MyEvent?.Invoke();
or:
obj?.SomeMethod();
The ?. is the null-propagating operator, and will cause the .Invoke() to be short-circuited when the operand is null. The operand is only ac...
How do you switch pages in Xamarin.Forms?
...thin a NavigationPage you should be able to access the Navigation property from within your page
– Jason
Aug 6 '14 at 21:28
1
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.NET HttpClient. How to POST string value?
...ome across. As if it were such a breeze to get it running if you're coming from a language with a proper IDE.
– Buffalo
Apr 1 '15 at 6:12
13
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How do I write stderr to a file while using “tee” with a pipe?
...mp;2)
We use process substitution again to make a tee process that reads from STDIN and dumps it into stderr.log. tee outputs its input back on STDOUT, but since its input is our STDERR, we want to redirect tee's STDOUT to our STDERR again. Then we use file redirection to redirect command's STDE...
Combining C++ and C - how does #ifdef __cplusplus work?
...lessly trapped inside of extern "C" regions, but it isn't such a good idea from a cleanliness perspective.
Now, specifically regarding your numbered questions:
Regarding #1: __cplusplus will stay defined inside of extern "C" blocks. This doesn't matter, though, since the blocks should nest neatly...
Why does X[Y] join of data.tables not allow a full outer join, or a left join?
...
To quote from the data.table FAQ 1.11 What is the difference between X[Y] and merge(X, Y)?
X[Y] is a join, looking up X's rows using Y (or Y's key if it has one) as an index.
Y[X] is a join, looking up Y's rows using X (or X'...
What is the purpose of wrapping whole Javascript files in anonymous functions like “(function(){ … }
...//I'm named!
}
}
In the above scenario, you can call globalFunction() from anywhere, but you cannot call localFunction1 or localFunction2.
What you're doing when you write (function() { ... })(), is you're making the code inside the first set of parentheses a function literal (meaning the whol...
Why doesn't Python have a sign function?
...
Floats hold "sign" separate from "value"; -0.0 is a negative number, even if that seems an implementation error. Simply using cmp() will give the desired results, probably for nearly every case anyone would care about: [cmp(zero, 0) for zero in (0, 0.0...
Haskell composition (.) vs F#'s pipe forward operator (|>)
... x // or x |> exp
to make it compile. This also steers people away from points-free/compositional style, and towards the pipelining style. Also, F# type inference sometimes demands pipelining, so that a known type appears on the left (see here).
(Personally, I find points-free style unread...