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What's the difference between SortedList and SortedDictionary?
...re any real practical difference between a SortedList<TKey,TValue> and a SortedDictionary<TKey,TValue> ? Are there any circumstances where you would specifically use one and not the other?
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How to make an alert dialog fill 90% of screen size?
I can create and display a custom alert dialog just fine but even so I have android:layout_width/height="fill_parent" in the dialog xml it is only as big as the contents.
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Reshaping data.frame from wide to long format
I have some trouble to convert my data.frame from a wide table to a long table.
At the moment it looks like this:
9 Answe...
How can I capture the result of var_dump to a string?
...Inwdr I've only ever used var_dump as a convenience feature for debugging, and have certainly never left var_dump statements in production code. I imagine this is typical. In those circumstances, performance is unlikely to be at all relevant.
– Mark Amery
Feb 2...
How to check if a map contains a key in Go?
...ng here
}
Explanation:
if statements in Go can include both a condition and an initialization statement. The example above uses both:
initializes two variables - val will receive either the value of "foo" from the map or a "zero value" (in this case the empty string) and ok will receive a bool ...
What is a void pointer in C++? [duplicate]
...ollowing:
It is dealing in unformatted memory. This is what operator new and malloc return: a pointer to a block of memory of a certain size. Since the memory does not have a type (because it does not have a properly constructed object in it yet), it is typeless. IE: void.
It is an opaque handle; ...
C char array initialization
...o
char buf[10] = {'a', 0, 0, 0, 0, 0, 0, 0, 0, 0};
As you can see, no random content: if there are fewer initializers, the remaining of the array is initialized with 0. This the case even if the array is declared inside a function.
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How to get a file or blob from an object URL?
...her methods. When an image is dropped, I'm using URL.createObjectURL to convert to an object URL to display the image. I am not revoking the url, as I do reuse it.
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How to create a MySQL hierarchical recursive query
... (select @pv := '19') initialisation
where find_in_set(parent_id, @pv)
and length(@pv := concat(@pv, ',', id))
Here is a fiddle.
Here, the value specified in @pv := '19' should be set to the id of the parent you want to select all the descendants of.
This will work also if a parent has m...
Throw keyword in function's signature
...ce this, so it has to be checked at runtime, which is usually undesirable. And it is not well supported in any case. (MSVC ignores exception specifications, except throw(), which it interprets as a guarantee that no exception will be thrown.
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