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How do I check for null values in JavaScript?
... !user){
Which will check for empty strings (""), null, undefined, false and the numbers 0 and NaN
Please note that if you are specifically checking for numbers it is a common mistake to miss 0 with this method, and num !== 0 is preferred (or num !== -1 or ~num (hacky code that also checks agains...
How to pass parameters on onChange of html select
I am a novice at JavaScript and jQuery. I want to show one combobox-A, which is an HTML <select> with its selected id and contents at the other place on onChange().
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Any difference between First Class Function and High Order Function
I'm wondering whether/what difference between First Class Function and High Order Function .
6 Answers
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Django development IDE [closed]
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I use Eclipse and a plain vanilla PyDev. There isn't any specific Django functionality. The best I came up with was setting up a run profile to run the development web server.
If you add the web tools project (WTP), you'll get syntax high...
Cleaning up the iPhone simulator
...o check:
"$HOME/Library/Developer/CoreSimulator/Devices"
The GUID files and directories match up to the simulator's installed apps.
Manually delete all those files/directories to remove all applications from the simulator.
I know there is some way to add scripts to the build process in XCode.
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Installing older version of R package
I am trying to use Rpy2 and ggplot2 but I get an error. After some searching for the error online, I found that the error occurs because there are changes in the ggplot2 package that are not yet reflected in Rpy2 (for example, see this post (Edit: Link is now dead)).
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Choosing a stand-alone full-text search server: Sphinx or SOLR? [closed]
I'm looking for a stand-alone full-text search server with the following properties:
5 Answers
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html5 - canvas element - Multiple layers
...ver, you could layer multiple <canvas> elements on top of each other and accomplish something similar.
<div style="position: relative;">
<canvas id="layer1" width="100" height="100"
style="position: absolute; left: 0; top: 0; z-index: 0;"></canvas>
<canvas id="layer...
Calculate distance between two latitude-longitude points? (Haversine formula)
How do I calculate the distance between two points specified by latitude and longitude?
41 Answers
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Simulator slow-motion animations are now on?
...as experimenting, trying to see if i could get navigation items to animate and scroll between each other.
11 Answers
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