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std::vector performance regression when enabling C++11
...lts are identical:
(I am compiling your original code, with container.push_back(Item());)
$ g++ -std=c++11 -O3 -flto regr.cpp && perf stat -r 10 ./a.out
Performance counter stats for './a.out' (10 runs):
35.426793 task-clock # 0.986 CPUs utilized (...
UIPanGestureRecognizer - Only vertical or horizontal
...t; fabs(velocity.x);
}
And for Swift:
func gestureRecognizerShouldBegin(_ gestureRecognizer: UIPanGestureRecognizer) -> Bool {
let velocity = gestureRecognizer.velocity(in: someView)
return abs(velocity.x) > abs(velocity.y)
}
...
Why do people use __(double underscore) so much in C++
...mming in C++, Rules and Recommendations :
The use of two underscores (`__') in identifiers is reserved for the compiler's internal use according to the ANSI-C standard.
Underscores (`_') are often used in names of library functions (such as "_main" and "_exit"). In order to avoid collisions...
In node.JS how can I get the path of a module I have loaded via require that is *not* mine (i.e. in
...'t want to) modify the module's code, so don't have a place to extract its __dirname.
7 Answers
...
What is SYSNAME data type in SQL Server?
...stored procedures etc within SQL Server.
For example, by executing Exec sp_help 'sys.tables' you will see that the column name is defined as sysname this is because the value of this is actually an object in itself (a table)
I would worry too much about it.
It's also worth noting that for those p...
How to assert output with nosetest/unittest in python?
... contextmanager
from StringIO import StringIO
@contextmanager
def captured_output():
new_out, new_err = StringIO(), StringIO()
old_out, old_err = sys.stdout, sys.stderr
try:
sys.stdout, sys.stderr = new_out, new_err
yield sys.stdout, sys.stderr
finally:
sys.s...
Timer function to provide time in nano seconds using C++
...repeatedly in a loop is correct.
For Linux (and BSD) you want to use clock_gettime().
#include <sys/time.h>
int main()
{
timespec ts;
// clock_gettime(CLOCK_MONOTONIC, &ts); // Works on FreeBSD
clock_gettime(CLOCK_REALTIME, &ts); // Works on Linux
}
For windows you want t...
Creating the Singleton design pattern in PHP5
...ctor so nobody else can instantiate it
*
*/
private function __construct()
{
}
}
To use:
$fact = UserFactory::Instance();
$fact2 = UserFactory::Instance();
$fact == $fact2;
But:
$fact = new UserFactory()
Throws an error.
See http://php.net/manual/en/language.variable...
Strip HTML from strings in Python
...
from html.parser import HTMLParser
class MLStripper(HTMLParser):
def __init__(self):
super().__init__()
self.reset()
self.strict = False
self.convert_charrefs= True
self.text = StringIO()
def handle_data(self, d):
self.text.write(d)
def g...
Change auto increment starting number?
In MySQL, I have a table, and I want to set the auto_increment value to 5 instead of 1 . Is this possible and what query statement does this?
...