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Why does Python code run faster in a function?
...e names are assigned to indexes. This is possible because you can't dynamically add local variables to a function. Then retrieving a local variable is literally a pointer lookup into the list and a refcount increase on the PyObject which is trivial.
Contrast this to a global lookup (LOAD_GLOBAL), w...
ERROR: Error installing capybara-webkit:
... path to where qt5 is installed. export QMAKE=/usr/local/Cellar/qt5/5.5.1_1/bin/qmake
– Seth Jeffery
Nov 16 '15 at 8:59
...
Can I return the 'id' field after a LINQ insert?
...? there is no insertonsubmit or submitchanges??
– Bat_Programmer
Jul 4 '12 at 0:35
1
@Confused Pr...
How to get current time and date in C++?
...
In C++ 11 you can use std::chrono::system_clock::now()
Example (copied from en.cppreference.com):
#include <iostream>
#include <chrono>
#include <ctime>
int main()
{
auto start = std::chrono::system_clock::now();
// Some computation ...
Update one MySQL table with values from another
...l named key such as id. ie an equi-join - http://en.wikipedia.org/wiki/Join_(SQL)#Equi-join
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rails 3 validation on uniqueness on multiple attributes
...
In Rails 2, I would have written:
validates_uniqueness_of :zipcode, :scope => :recorded_at
In Rails 3:
validates :zipcode, :uniqueness => {:scope => :recorded_at}
For multiple attributes:
validates :zipcode, :uniqueness => {:scope => [:recorded_at...
TypeScript type signatures for functions with variable argument counts
...prototype for the function as well as the function, thus:-
function format_n(str: string, ... $n: any[]): string;
function format_n(str: string): string {
return str.replace(/%(\d+)/g, (_, n) => format_n.arguments[n]);
}
...
Send email using the GMail SMTP server from a PHP page
...
// Pear Mail Library
require_once "Mail.php";
$from = '<fromaddress@gmail.com>';
$to = '<toaddress@yahoo.com>';
$subject = 'Hi!';
$body = "Hi,\n\nHow are you?";
$headers = array(
'From' => $from,
'To' => $to,
'Subject' =&...
Easily measure elapsed time
...
//***C++11 Style:***
#include <chrono>
std::chrono::steady_clock::time_point begin = std::chrono::steady_clock::now();
std::chrono::steady_clock::time_point end = std::chrono::steady_clock::now();
std::cout << "Time difference = " << std::chrono::duration_cast<std::c...
How to get current moment in ISO 8601 format with date, hour, and minute?
...ad safe.
ZonedDateTime.now( ZoneOffset.UTC ).format( DateTimeFormatter.ISO_INSTANT )
Result: 2015-04-14T11:07:36.639Z
You may be tempted to use lighter Temporal such as Instant or LocalDateTime,
but they lacks formatter support or time zone data.
Only ZonedDateTime works out of the box.
...