大约有 46,000 项符合查询结果（耗时：0.0623秒） [XML]
@selector() in Swift?
... for: .touchUpInside)
view.perform(#selector(UIView.insertSubview(_:aboveSubview:)),
with: button, with: otherButton)
The great thing about this approach? A function reference is checked by the Swift compiler, so you can use the #selector expression only with class/method pair...
What's the difference between HEAD^ and HEAD~ in Git?
...f thumb
Use ~ most of the time — to go back a number of generations, usually what you want
Use ^ on merge commits — because they have two or more (immediate) parents
Mnemonics:
Tilde ~ is almost linear in appearance and wants to go backward in a straight line
Caret ^ suggests an interesting s...
Default parameters with C++ constructors [closed]
...ks in their favor.
One thing to watch out for is if you have defaults for all but one parameter, your class can be implicitly converted from that parameter type. Check out this thread for more info.
share
|
...
How does this milw0rm heap spraying exploit work?
I usually do not have difficulty to read JavaScript code but for this one I can’t figure out the logic. The code is from an exploit that has been published 4 days ago. You can find it at milw0rm .
...
SQL Server: Filter output of sp_who2
Under SQL Server, is there an easy way to filter the output of sp_who2? Say I wanted to just show rows for a certain database, for example.
...
Are Swift variables atomic?
... you, i.e.:
class Car {
static let sharedCar: Car = Car() // will be called inside of dispatch_once
}
private let sharedCar: Car2 = Car2() // same here
class Car2 {
}
Update 05/25/16: Keep an eye out for swift evolution proposal https://github.com/apple/swift-evolution/blob/master/proposals...
What is the colon operator in Ruby?
..." # false
:foo.equal? :foo # true
This makes comparing two symbols really fast (since only a pointer comparison is involved, as opposed to comparing all the characters like you would in a string), plus you won't have a zillion copies of the same symbol floating about.
Also, unlike strings, sy...
Why is a round-trip conversion via a string not safe for a double?
...ber(value, 17, &number);
DoubleToNumber is pretty simple -- it just calls _ecvt, which is in the C runtime:
void DoubleToNumber(double value, int precision, NUMBER* number)
{
WRAPPER_CONTRACT
_ASSERTE(number != NULL);
number->precision = precision;
if (((FPDOUBLE*)&val...
Why does struct alignment depend on whether a field type is primitive or user-defined?
... The documentation of StructLayoutAttribute is pretty interesting. Basically, only blittable types are controlled through StructLayout in managed memory. Interesting, never knew that.
– Michael Stum♦
Jul 15 '14 at 7:01
...
How to convert 2D float numpy array to 2D int numpy array?
...(int), np.array([-np.inf]).astype(int), and np.array([np.nan]).astype(int) all return the same thing. Why?
– BallpointBen
May 14 '18 at 20:47
1
...