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How to check if array is empty or does not exist? [duplicate]
...ether its argument is an array. This weeds out values like null, undefined and anything else that is not an array.
Note that this will also eliminate array-like objects, such as the arguments object and DOM NodeList objects. Depending on your situation, this might not be the behavior you're after.
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How to check whether a file or directory exists?
...(err) { return false, nil }
return false, err
}
Edited to add error handling.
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Run an app on a multiple devices automatically in Android Studio
I have a multiple Android devices connected to the computer. When I try to run the app I'm developing, the Android Studio always prompt me to choose the device. Is there any way to deploy the app on a multiple devices automatically - by clicking Run or even better with a shortcut?
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Where does npm install packages?
...aries
You can run npm list -g to see which global libraries are installed and where they're located. Use npm list -g | head -1 for truncated output showing just the path. If you want to display only main packages not its sub-packages which installs along with it - you can use - npm list --depth=0 w...
What's the difference between git clone --mirror and git clone --bare
...es of the target, it maps all refs (including remote branches, notes etc.) and sets up a refspec configuration such that all these refs are overwritten by a git remote update in the target repository.
My original answer also noted the differences between a bare clone and a normal (non-bare) clone ...
Use Font Awesome icon as CSS content
...Thanks to Aurelien
You need to change the font-family to Font Awesome 5 Brands OR Font Awesome 5 Free, based on the type of icon you are trying to render. Also, do not forget to declare font-weight: 900;
a:before {
font-family: "Font Awesome 5 Free";
content: "\f095";
display: inline-bloc...
Understanding reference counting with Cocoa and Objective-C
I'm just beginning to have a look at Objective-C and Cocoa with a view to playing with the iPhone SDK. I'm reasonably comfortable with C's malloc and free concept, but Cocoa's references counting scheme has me rather confused. I'm told it's very elegant once you understand it, but I'm just not o...
What are the benefits of learning Vim? [closed]
As a programmer I spend a lot of hours at the keyboard and I've been doing it for the last 12 years, more or less. If there's something I've never gotten used to during all this time, it's these annoying and almost unconscious constant micro-interruptions I experience while coding, due to some of th...
Check number of arguments passed to a Bash script
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Just like any other simple command, [ ... ] or test requires spaces between its arguments.
if [ "$#" -ne 1 ]; then
echo "Illegal number of parameters"
fi
Or
if test "$#" -ne 1; then
echo "Illegal number of parameters"
fi
Suggestions
When in Bash,...
Python function attributes - uses and abuses [closed]
Not many are aware of this feature, but Python's functions (and methods) can have attributes . Behold:
8 Answers
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