大约有 45,000 项符合查询结果(耗时:0.0715秒) [XML]
dealloc in Swift
...an-up
yourself. For example, if you create a custom class to open a file and
write some data to it, you might need to close the file before the
class instance is deallocated.
share
|
improve ...
Why does SIGPIPE exist?
From my understanding, SIGPIPE can only occur as the result of a write() , which can (and does) return -1 and set errno to EPIPE ... So why do we have the extra overhead of a signal? Every time I work with pipes I ignore SIGPIPE and have never felt any pain as a result, am I missing somethin...
Why do some functions have underscores “__” before and after the function name?
This "underscoring" seems to occur a lot, and I was wondering if this was a requirement in the Python language, or merely a matter of convention?
...
Best way to find the intersection of multiple sets?
...e", what you are looking for is the reduce function:
from operator import and_
from functools import reduce
print(reduce(and_, [{1,2,3},{2,3,4},{3,4,5}])) # = {3}
or
print(reduce((lambda x,y: x&y), [{1,2,3},{2,3,4},{3,4,5}])) # = {3}
...
How can I have two fixed width columns with one flexible column in the center?
I'm trying to set up a flexbox layout with three columns where the left and right columns have a fixed width, and the center column flexes to fill the available space.
...
When to use nested classes and classes nested in modules?
I'm pretty familiar with when to use subclasses and modules, but more recently I've been seeing nested classes like this:
5...
Pointer to class data member “::*”
...nest, I've never had to use them in my own code.
Edit: I can't think off-hand of a convincing use for pointers to member data. Pointer to member functions can be used in pluggable architectures, but once again producing an example in a small space defeats me. The following is my best (untested) tr...
Best way to extract a subvector from a vector?
... +1, also it's O(Y-X), which is less than or equal to O(N) (and in his example much less)
– orip
Jan 7 '09 at 21:53
78
...
in_array multiple values
...
Intersect the targets with the haystack and make sure the intersection is precisely equal to the targets:
$haystack = array(...);
$target = array('foo', 'bar');
if(count(array_intersect($haystack, $target)) == count($target)){
// all of $target is in $haysta...
Why does an NSInteger variable have to be cast to long when used as a format argument?
...le on OS X (64-bit), because on that platform NSInteger is defined as long and is a 64-bit integer. The %i format, on the other hand, is for int, which is 32-bit. So the format and the actual parameter do not match in size.
Since NSInteger is 32-bit or 64-bit, depending on the platform, the compile...