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Nullable vs. int? - Is there any difference?
Apparently Nullable<int> and int? are equivalent in value. Are there any reasons to choose one over the other?
5 ...
Possible to do a MySQL foreign key to one of two possible tables?
...which target table is referenced.
CREATE TABLE popular_places (
user_id INT NOT NULL,
place_id INT NOT NULL,
place_type VARCHAR(10) -- either 'states' or 'countries'
-- foreign key is not possible
);
There's no way to model Polymorphic Associations using SQL constraints. A foreign key co...
Comma in C/C++ macro
...rs.) You can enclose the macro argument in parentheses:
FOO((std::map<int, int>), map_var);
The problem is then that the parameter remains parenthesized inside the macro expansion, which prevents it being read as a type in most contexts.
A nice trick to workaround this is that in C++, you...
Use of 'const' for function parameters
...lot though.
I personally tend to not use const except for reference and pointer parameters. For copied objects it doesn't really matter, although it can be safer as it signals intent within the function. It's really a judgement call. I do tend to use const_iterator though when looping on something ...
“inconsistent use of tabs and spaces in indentation”
...s and spaces in indentation error and select:
view > indentation > convert indentation to spaces
which resolved the issue for me.
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Is gcc's __attribute__((packed)) / #pragma pack unsafe?
...he x86, misaligned accesses are handled in hardware; if you dereference an int* pointer that points to an odd address, it will be a little slower than if it were properly aligned, but you'll get the correct result.)
On some other systems, such as SPARC, attempting to access a misaligned int object ...
Why does an image captured using camera intent gets rotated on some devices on Android?
...o it will work in most cases, but it is not a 100% reliable solution.
ExifInterface ei = new ExifInterface(photoPath);
int orientation = ei.getAttributeInt(ExifInterface.TAG_ORIENTATION,
ExifInterface.ORIENTATION_UNDEFINED);
Bitmap rotatedBitmap = null;
switch(...
How can I make an EXE file from a Python program? [duplicate]
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Auto PY to EXE - A .py to .exe converter using a simple graphical interface built using Eel and PyInstaller in Python.
py2exe is probably what you want, but it only works on Windows.
PyInstaller works on Windows and Linux.
Py2app works on the Mac.
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What is the difference between JDK and JRE?
...rver. Why would you need the JDK then? Because the application server will convert JSP into Java servlets and needs to use the JDK to compile the servlets. I am sure that there are more examples.
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Best way to merge two maps and sum the values of same key?
...al map1 = Map(1 -> 9 , 2 -> 20)
map1: scala.collection.immutable.Map[Int,Int] = Map(1 -> 9, 2 -> 20)
scala> val map2 = Map(1 -> 100, 3 -> 300)
map2: scala.collection.immutable.Map[Int,Int] = Map(1 -> 100, 3 -> 300)
scala> map1 |+| map2
res2: scala.collection.immutable...