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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...
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...
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...
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...rces of time zone boundary data, but are no longer actively maintained.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...
Python pandas: fill a dataframe row by row
... I see. So the loc attribute of the data frame defines a special __setitem__ that does the magic I suppose.
– xApple
Jun 13 '13 at 16:24
...
How do I check if an array includes a value in JavaScript?
...ilar methods:
jQuery: $.inArray(value, array, [fromIndex])
Underscore.js: _.contains(array, value) (also aliased as _.include and _.includes)
Dojo Toolkit: dojo.indexOf(array, value, [fromIndex, findLast])
Prototype: array.indexOf(value)
MooTools: array.indexOf(value)
MochiKit: findValue(array, val...
How to get GET (query string) variables in Express.js on Node.js?
...et the variables in the query string in Node.js just like we get them in $_GET in PHP?
26 Answers
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