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not None test in Python [duplicate]
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if val is not None:
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is the Pythonic idiom for testing that a variable is not set to None. This idiom has particular uses in the case of declaring keyword functions with default parameters. is tests identity in Python. Because there is one and only one instance of None presen...
Does Java support default parameter values?
I came across some Java code that had the following structure:
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Find and restore a deleted file in a Git repository
Say I'm in a Git repository. I delete a file and commit that change. I continue working and make some more commits. Then, I find I need to restore that file.
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How do I check for null values in JavaScript?
How can I check for null values in JavaScript? I wrote the code below but it didn't work.
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Echo tab characters in bash script
How do I echo one or more tab characters using a bash script?
When I run this code
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Converting a JS object to an array using jQuery
My application creates a JavaScript object, like the following:
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Determining Whether a Directory is Writeable
What would be the best way in Python to determine whether a directory is writeable for the user executing the script? Since this will likely involve using the os module I should mention I'm running it under a *nix environment.
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Javascript regex returning true.. then false.. then true.. etc [duplicate]
I have a strange problem with the validation I am writing on a form. It is a 'Check Username' button next to an input. The input default value is the username for example 'betamax'. When I press 'Check Username' it passes the regex and sends the username to the server. The server behaves as expected...
How can I force a hard reload in Chrome for Android
In Chrome for desktop I have options in the dev tools to disable cache completely when dev tools are opened and I have the options to manually do a hard reload when long clicking on the reload button (with dev tools open).
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How do I run a shell script without using “sh” or “bash” commands?
I have a shell script which I want to run without using the "sh" or "bash" commands. For example:
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