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How to add target=“_blank” to JavaScript window.location?
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@BenRacicot well yes, popups are blocked by default and most people don't change that
– twinlakes
Nov 5 '15 at 0:11
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Logging framework incompatibility
I'm building a small Java app and hoping to use logback for logging.
3 Answers
3
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Replace one character with another in Bash
...lexity is worse than linear. A small test: x="$(tr -dc 'a-z \n' </dev/urandom | head -c1M)"; time y="$(tr ' ' \\- <<< "$x")"; time z="${x// /-}". With a string length of 1M (=2^20) tr took 0.04s and bash 5.0.11 took 17s. With 2M tr took 0.07s (expected) but bash took 69s (4 times as lon...
Why does the JavaScript need to start with “;”?
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I would say since scripts are often concatenated and minified/compressed/sent together there's a chance the last guy had something like:
return {
'var':'value'
}
at the end of the last script without a ; on the end. If you have a ; at the start on yours, it's safe, e...
To find whether a column exists in data frame or not
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Assuming that the name of your data frame is dat and that your column name to check is "d", you can use the %in% operator:
if("d" %in% colnames(dat))
{
cat("Yep, it's in there!\n");
}
share
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Ruby, Difference between exec, system and %x() or Backticks
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The system method calls a system program. You have to provide the command as a string argument to this method. For example:
>> system("date")
Wed Sep 4 22:03:44 CEST 2013
=> true
The invoked program will use the current STDIN, STDOUT and STDERR objects of your Ruby program. In fact...
Difference between Visibility.Collapsed and Visibility.Hidden
What are differences between Visibility.Collapsed and Visibility.Hidden in WPF?
3 Answers
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What is the 'cls' variable used for in Python classes?
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The distinction between "self" and "cls" is defined in PEP 8 . As Adrien said, this is not a mandatory. It's a coding style. PEP 8 says:
Function and method arguments:
Always use self for the first argument to instance methods.
Always use cls for the firs...
Where does Jenkins store configuration files for the jobs it runs?
...itself is kept on an EC2 machine - one that might need to be taken offline and brought back on an entirely different EC2 instance at any point. We have a bunch of Puppet manifests allowing us to easily reinstall the software on the EC2 instance, but custom configuration files, like the ones for the ...
How do I access the request object or any other variable in a form's clean() method?
...gument, request. This stores the request in the form, where it's required, and from where you can access it in your clean method.
class MyForm(forms.Form):
def __init__(self, *args, **kwargs):
self.request = kwargs.pop('request', None)
super(MyForm, self).__init__(*args, **kwar...