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Difference between == and ===
...Swift also provides two identity operators (=== and !==), which you use to test whether two object references both refer to the same object instance.
Excerpt From: Apple Inc. “The Swift Programming Language.” iBooks. https://itun.es/us/jEUH0.l
...
Spring Boot JPA - configuring auto reconnect
... the following to your application.properties up to 1.3
spring.datasource.testOnBorrow=true
spring.datasource.validationQuery=SELECT 1
As djxak noted in the comment, 1.4+ defines specific namespaces for the four connections pools Spring Boot supports: tomcat, hikari, dbcp, dbcp2 (dbcp is deprecat...
How to Compare Flags in C#?
....NET 4 there is a new method Enum.HasFlag. This allows you to write:
if ( testItem.HasFlag( FlagTest.Flag1 ) )
{
// Do Stuff
}
which is much more readable, IMO.
The .NET source indicates that this performs the same logic as the accepted answer:
public Boolean HasFlag(Enum flag) {
if (!t...
MongoDB/NoSQL: Keeping Document Change History
...value: "This is the new body" }
],
tags: [
{ version: 1, value: [ "test", "trivial" ] },
{ version: 6, value: [ "foo", "test" ] }
],
comments: [
{
author: "joe", // Unversioned field
body: [
{ version: 3, value: "Something cool" }
]
},
{
au...
simple HTTP server in Java using only Java SE API
...erver.HttpHandler;
import com.sun.net.httpserver.HttpServer;
public class Test {
public static void main(String[] args) throws Exception {
HttpServer server = HttpServer.create(new InetSocketAddress(8000), 0);
server.createContext("/test", new MyHandler());
server.setEx...
Creating a daemon in Linux
...e mask according to the needs of the daemon.
close - Close all open file descriptors that may be inherited from the parent process.
To give you a starting point: Look at this skeleton code that shows the basic steps. This code can now also be forked on GitHub: Basic skeleton of a linux daemon
/...
Change navbar color in Twitter Bootstrap
...-color: $bgHighlight; }}}
}
And finally, a little gift
I've just made a script which will allow you to generate your theme:
TWBSColor - Generate your own Bootstrap navbar
[Update]: TWBSColor now generates SCSS/SASS/Less/CSS code.
[Update]: From now, you can use Less as the default language prov...
Test if string is a number in Ruby on Rails
...cases expected.
If they are relatively uncommon casting is definitely fastest.
If false cases are common and you are just checking for ints, comparison vs a transformed state is a good option.
If false cases are common and you are checking floats, regexp is probably the way to go
If performance ...
Temporarily disable auto_now / auto_now_add
...
I've recently faced this situation while testing my application. I needed to "force" an expired timestamp. In my case I did the trick by using a queryset update. Like this:
# my model
class FooBar(models.Model):
title = models.CharField(max_length=255)
upda...
How to remove unused C/C++ symbols with GCC and ld?
...unreferenced sections):
-Wl,--gc-sections
So if you had one file called test.cpp that had two functions declared in it, but one of them was unused, you could omit the unused one with the following command to gcc(g++):
gcc -Os -fdata-sections -ffunction-sections test.cpp -o test -Wl,--gc-sections...