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?: operator (the 'Elvis operator') in PHP
...will leave foo unchanged.
Some more examples:
<?php
var_dump(5 ?: 0); // 5
var_dump(false ?: 0); // 0
var_dump(null ?: 'foo'); // 'foo'
var_dump(true ?: 123); // true
var_dump('rock' ?: 'roll'); // 'rock'
?>
By the way, it's called the Elvis operator.
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How to loop through all but the last item of a list?
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answered May 27 '09 at 9:04
freespacefreespace
15.1k33 gold badges3434 silver badges5555 bronze badges
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Check that an email address is valid on iOS [duplicate]
...ng
{
BOOL stricterFilter = NO; // Discussion http://blog.logichigh.com/2010/09/02/validating-an-e-mail-address/
NSString *stricterFilterString = @"^[A-Z0-9a-z\\._%+-]+@([A-Za-z0-9-]+\\.)+[A-Za-z]{2,4}$";
NSString *laxString = @"^.+@([A-Za-z0-9-]+\\.)+[A-Za-z]{2}[A-Za-z]*$";
NSString *ema...
SQL Server 2008 Windows Auth Login Error: The login is from an untrusted domain
When attempting to connect to a SQL Server 2008 Instance using Management Studio, I get the following error:
35 Answers
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How does a UILabel's minimumScaleFactor work?
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205
You need to set the label.adjustsFontSizeToFitWidth = YES;
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Given an RGB value, how do I create a tint (or shade)?
Given an RGB value, like 168, 0, 255 , how do I create tints (make it lighter) and shades (make it darker) of the color?
3...
Convert RGBA PNG to RGB with PIL
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130
Here's a version that's much simpler - not sure how performant it is. Heavily based on some djan...
What is the Python 3 equivalent of “python -m SimpleHTTPServer”
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1850
From the docs:
The SimpleHTTPServer module has been merged into http.server in Python 3.0. T...
How to activate JMX on my JVM for access with jconsole?
...rs:
-Dcom.sun.management.jmxremote
-Dcom.sun.management.jmxremote.port=9010
-Dcom.sun.management.jmxremote.rmi.port=9010
-Dcom.sun.management.jmxremote.local.only=false
-Dcom.sun.management.jmxremote.authenticate=false
-Dcom.sun.management.jmxremote.ssl=false
For instance like this:
java -Dcom...
Is there a way to list pip dependencies/requirements?
...m providing an updated answer.
This was tested with pip versions 8.1.2, 9.0.1, 10.0.1, and 18.1.
To get the output without cluttering your current directory on Linux use
pip download [package] -d /tmp --no-binary :all: -v
-d tells pip the directory that download should put files in.
Better, ju...