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How do I tell if a regular file does not exist in Bash?
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The test command ([ here) has a "not" logical operator which is the exclamation point (similar to many other languages). Try this:
if [ ! -f /tmp/foo.txt ]; then
echo "File not found!"
fi
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How to align input forms in HTML
I'm new to HTML and I'm trying to learn how to use forms.
16 Answers
16
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How to import the class within the same directory or sub directory?
...es are in a subdirectory - put an __init__.py in the subdirectory as well, and then use regular import statements, with dot notation. For each level of directory, you need to add to the import path.
bin/
main.py
classes/
user.py
dir.py
So if the directory was named "class...
Can I pass parameters by reference in Java?
...itself which is passed by value, hence it appears to be pass-by-reference (and people often claim that it is). This is not the case, as shown by the following:
Object o = "Hello";
mutate(o)
System.out.println(o);
private void mutate(Object o) { o = "Goodbye"; } //NOT THE SAME o!
Will print Hello...
Can I use a :before or :after pseudo-element on an input field?
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:after and :before are not supported in Internet Explorer 7 and under, on any elements.
It's also not meant to be used on replaced elements such as form elements (inputs) and image elements.
In other words it's impossible with pur...
How to avoid circular imports in Python? [duplicate]
...know the issue of circular imports in python has come up many times before and I have read these discussions. The comment that is made repeatedly in these discussions is that a circular import is a sign of a bad design and the code should be reorganised to avoid the circular import.
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How can I view all the git repositories on my machine?
...which I can see all the git repositories that exist on my machine? Any command for that?
10 Answers
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Looping a video with AVFoundation AVPlayer?
...ect as? AVPlayerItem {
playerItem.seek(to: CMTime.zero, completionHandler: nil)
}
}
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Why am I seeing an “origin is not allowed by Access-Control-Allow-Origin” error here? [duplicate]
...quests outside of the current domain.
Ex 1: your domain is example.com and you want to make a request to test.com => you cannot.
Ex 2: your domain is example.com and you want to make a request to inner.example.com => you cannot.
Ex 3: your domain is example.com:80 and you want to make a...
Is it possible to specify a different ssh port when using rsync?
I have been attempting the following command:
8 Answers
8
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