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How to forward declare a template class in namespace std?
...served for use by the implementation, so you should use something like TEST_H instead of __TEST__. It's not going to generate a warning or an error, but if your program has a clash with an implementation-defined identifier, then it's not guaranteed to compile or run correctly: it's ill-formed. Also ...
Why can't I define a default constructor for a struct in .NET?
...ublic struct Tempo
{
const double DefaultBpm = 120;
private double _bpm; // this field must not be modified other than with its property.
public double BeatsPerMinute
{
get => _bpm + DefaultBpm;
set => _bpm = value - DefaultBpm;
}
}
This is different than...
Can I call memcpy() and memmove() with “number of bytes” set to zero?
...
From the C99 standard (7.21.1/2):
Where an argument declared as size_t n specifies the length of the array for a
function, n can have the value zero on a call to that function. Unless explicitly stated
otherwise in the description of a particular function in this subclause, pointer argume...
What kind of leaks does automatic reference counting in Objective-C not prevent or minimize?
...chain referring back to an earlier object.
It is for this reason that the __unsafe_unretained and __weak ownership qualifiers exist. The former will not retain any object it points to, but leaves open the possibility of that object going away and it pointing to bad memory, whereas the latter doesn...
What is a “callback” in C and how are they implemented?
...y're implemented using function pointers. Here's an example:
void populate_array(int *array, size_t arraySize, int (*getNextValue)(void))
{
for (size_t i=0; i<arraySize; i++)
array[i] = getNextValue();
}
int getNextRandomValue(void)
{
return rand();
}
int main(void)
{
int m...
Why does the MongoDB Java driver use a random number generator in a conditional?
... laws it is a trivial observation that this piece of code amounts to
if (!_ok && Math.random() <= 0.1)
return res;
The commit that originally introduced this logic had
if (_ok == true) {
_logger.log( Level.WARNING , "Server seen down: " + _addr, e );
} else if (Math.random() < 0...
Django South - table already exists
...
Although the table "myapp_tablename" already exists error stop raising
after I did ./manage.py migrate myapp --fake, the DatabaseError shows
no such column: myapp_mymodel.added_field.
Got exactly the same problem!
1.Firstly check the migration...
Best way to assert for numpy.array equality?
...some unit-tests for my app, and I need to compare two arrays. Since array.__eq__ returns a new array (so TestCase.assertEqual fails), what is the best way to assert for equality?
...
Windows batch: echo without new line
...d $write.special (
<nul set /p "=!%~1!"
exit /b
)
>"%$write.temp%_1.txt" (echo !str!!$write.sub!)
copy "%$write.temp%_1.txt" /a "%$write.temp%_2.txt" /b >nul
type "%$write.temp%_2.txt"
del "%$write.temp%_1.txt" "%$write.temp%_2.txt"
set "str2=!str:*%$write.sub%=%$write.sub%!"
if "!str2!...
How to get a time zone from a location using latitude and longitude coordinates?
...rces of time zone boundary data, but are no longer actively maintained.
tz_world - the original shapefile data from Eric Muller
whereonearth-timezone - GeoJSON version with WOEDB data merged in
Time Zone Geolocation Offline Implementations
Implementations that use the Timezone Boundary Builder dat...