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Why do I get AttributeError: 'NoneType' object has no attribute 'something'?
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NoneType means that instead of an instance of whatever Class or Object you think you're working with, you've actually got None. That usually means that an assignment or function call up above failed or returned an unexpected result.
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Sorting a tab delimited file
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Using bash, this will do the trick:
$ sort -t$'\t' -k3 -nr file.txt
Notice the dollar sign in front of the single-quoted string. You can read about
it in the ANSI-C Quoting sections of the bash man page.
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Microsoft Web API: How do you do a Server.MapPath?
Since Microsoft Web API isn't MVC , you cannot do something like this:
7 Answers
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Grep regex NOT containing string
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grep matches, grep -v does the inverse. If you need to "match A but not B" you usually use pipes:
grep "${PATT}" file | grep -v "${NOTPATT}"
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Why should hash functions use a prime number modulus?
A long time ago, I bought a data structures book off the bargain table for $1.25. In it, the explanation for a hashing function said that it should ultimately mod by a prime number because of "the nature of math".
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How can I update npm on Windows?
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This is the new best way to upgrade npm on Windows.
Run PowerShell as Administrator
Set-ExecutionPolicy Unrestricted -Scope CurrentUser -Force
npm install -g npm-windows-upgrade
npm-windows-upgrade
Note: Do not run npm i -g npm. Instead use npm-window...
How do I get bash completion to work with aliases?
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As stated in the comments above,
complete -o default -o nospace -F _git_checkout gco
will no longer work. However, there's a __git_complete function in git-completion.bash which can be used to set up completion for aliases like so:
__git_complete gco _git_checkout
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Convert array of integers to comma-separated string
It's a simple question; I am a newbie in C#, how can I perform the following
5 Answers
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How to specify the order of CSS classes?
I'm a little confused about CSS and the class attribute. I always thought, the order in which I specify multiple classes in the attribute value has a meaning. The later class could/should overwrite definitions of the previous, but this doesn't seem to work. Here's an example:
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How do I determine the size of an object in Python?
I want to know how to get size of objects like a string, integer, etc. in Python.
13 Answers
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