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Is there a VB.NET equivalent of C# out parameters?
...rect equivalent to C# out function parameters, where the variable passed into a function does not need to be initialised?
...
Full Screen DialogFragment in Android
...
void showDialog() {
FragmentTransaction ft = getFragmentManager().beginTransaction();
DialogFragment newFragment = MyDialogFragment.newInstance();
newFragment.show(ft, "dialog");
}
public static class MyDialogFragment extends DialogFragment {
static MyDialogFragment newInstance()...
Releasing memory in Python
...e heap can be subject to high-water marks. This is complicated by Python's internal optimizations for allocating small objects (PyObject_Malloc) in 4 KiB pools, classed for allocation sizes at multiples of 8 bytes -- up to 256 bytes (512 bytes in 3.3). The pools themselves are in 256 KiB arenas, so ...
What's the @ in front of a string in C#?
... a verbatim string literal - anything in the string that would normally be interpreted as an escape sequence is ignored.
So "C:\\Users\\Rich" is the same as @"C:\Users\Rich"
There is one exception: an escape sequence is needed for the double quote. To escape a double quote, you need to put two dou...
Use cases for the 'setdefault' dict method
...f it's dynamic.
For example, I need a dictionary to map strings to unique ints. defaultdict(int) will always use 0 for the default value. Likewise, defaultdict(intGen()) always produces 1.
Instead, I used a regular dict:
nextID = intGen()
myDict = {}
for lots of complicated stuff:
#stuff that...
Javascript: negative lookbehind equivalent?
...
Lookbehind Assertions got accepted into the ECMAScript specification in 2018.
Positive lookbehind usage:
console.log(
"$9.99 €8.47".match(/(?<=\$)\d+(\.\d*)?/) // Matches "9.99"
);
Negative lookbehind usage:
console.log(
"$9.99 ...
Why is there “data” and “newtype” in Haskell? [duplicate]
...
Both newtype and the single-constructor data introduce a single value constructor, but the value constructor introduced by newtype is strict and the value constructor introduced by data is lazy. So if you have
data D = D Int
newtype N = N Int
Then N undefined is equ...
SQL Switch/Case in 'where' clause
...
declare @locationType varchar(50);
declare @locationID int;
SELECT column1, column2
FROM viewWhatever
WHERE
@locationID =
CASE @locationType
WHEN 'location' THEN account_location
WHEN 'area' THEN xxx_location_area
WHEN 'division' THEN xxx_location_division ...
Why do loggers recommend using a logger per class?
...to clarify things. We were just manually putting the class name and method into the message (i.e. "ImageCreator.CreateThumbnail() called"), but it's better if the logger can handle it.
– Daniel T.
Jun 30 '10 at 19:40
...
What is the difference between a weak reference and an unowned reference?
... reference whenever it is valid for that reference to become
nil at some point during its lifetime. Conversely, use an unowned
reference when you know that the reference will never be nil once it
has been set during initialization.
In the docs, there are some examples that discuss retain cycles and...