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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 ...
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...
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...
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 ...
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 do I perform an insert and return inserted identity with Dapper?
...his case the simpler option is simply:
var id = connection.QuerySingle<int>( @"
INSERT INTO [MyTable] ([Stuff]) VALUES (@Stuff);
SELECT CAST(SCOPE_IDENTITY() as int)", new { Stuff = mystuff});
Note that on more recent versions of SQL Server you can use the OUTPUT clause:
var id = connectio...
Union of dict objects in Python [duplicate]
...
Why converting to list() ? def union2(dict1, dict2): return dict(dict1.items() + dict2.items())
– kinORnirvana
May 22 '17 at 14:48
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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...
HashMap and int as key
I am trying to build a HashMap which will have integer as keys and objects as values.
11 Answers
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