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What reason is there to use null instead of undefined in JavaScript?
I've been writing JavaScript for quite a long time now, and I have never had a reason to use null . It seems that undefined is always preferable and serves the same purpose programmatically. What are some practical reasons to use null instead of undefined ?
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C++ static virtual members?
...what would happen when you called Object::GetTypeInformation()? It can't know which derived class version to call since there's no object associated with it.
You'll have to make it a non-static virtual function to work properly; if you also want to be able to call a specific derived class's versio...
How to install mongoDB on windows?
...loaded the 32bit windows version, but have no idea on how to continue from now on.
15 Answers
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Get the device width in javascript
...max-width value of the html tag:
maxwidth = $('html').css('max-width');
Now you can use this value to make conditional changes:
If (maxwidth == '480px') { do something }
If putting the max-width value on the html tag seems scary, then maybe you can put on a different tag, one that is only used...
How to run multiple Python versions on Windows
... name given. When it finds the correct file to run the file is being run.
Now, if you've installed two python versions 2.5 and 2.6, the path will have both of their directories in it, something like PATH=c:\python\2.5;c:\python\2.6 but Windows will stop examining the path when it finds a match.
Wh...
Incrementing a date in JavaScript
...t anything they wanted to in Date.parse. The new 5th edition specification now has a minimum format that must be accepted, but I wouldn't count on that yet.
– T.J. Crowder
Sep 9 '10 at 8:18
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How to put a UserControl into Visual Studio toolBox
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In VS2012 they have now added the hint 'The current solution must be re-opened for this to take effect' to the options dialog.
– Carlos P
Nov 28 '13 at 20:08
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ignoring any 'bin' directory on a git project
...won't stop tracking paths that are already being tracked just because they now match a new .gitignore pattern. Execute a folder remove (rm) from index only (--cached) recursivelly (-r). Command line example for root bin folder:
git rm -r --cached bin
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Bash: Strip trailing linebreak from output
... My up-vote is for the head -c ... version -- Because I can now feed commands to the clipboard and preserve formatting, but for the last \n. Eg.: alias clip="head -c -1 | xclip -selection clipboard", not too shabby. Now when you pipe ls -l | clip ... All that wonderful output goes ...
When to use single quotes, double quotes, and backticks in MySQL
...write queries. I also understand the importance of being consistent. Until now, I have randomly used single quotes, double quotes, and backticks without any real thought.
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