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How to check for an undefined or null variable in JavaScript?
...xistingObj.someUndefProperty. An undefined property doesn't yield an error and simply returns undefined, which, when converted to a boolean, evaluates to false. So, if you don't care about
0 and false, using if(obj.undefProp) is ok. There's a common idiom based on this fact:
value = obj.prop || de...
Android: How to stretch an image to the screen width while maintaining aspect ratio?
...to download an image (of unknown size, but which is always roughly square) and display it so that it fills the screen horizontally, and stretches vertically to maintain the aspect ratio of the image, on any screen size. Here is my (non-working) code. It stretches the image horizontally, but not vert...
How to use sed to replace only the first occurrence in a file?
...r if you prefer' solution. It would also be good to explain the answers - and to make the answer address the question directly, and then generalize, rather than generalize only. But good answer.
– Jonathan Leffler
Sep 29 '08 at 13:15
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What's the best visual merge tool for Git? [closed]
What's the best tool for viewing and editing a merge in Git? I'd like to get a 3-way merge view, with "mine", "theirs" and "ancestor" in separate panels, and a fourth "output" panel.
...
Constructors vs Factory Methods [closed]
...ns: Elements of Reusable Object-Oriented Software by Gamma, Helm, Johnson, and Vlissides.
Use the Factory Method pattern when
a class can't anticipate the class of objects it must create
a class wants its subclasses to specify the objects it creates
classes delegate responsibility to one of sever...
Windows threading: _beginthread vs _beginthreadex vs CreateThread C++
...ulate that MS originally intended the _begin routines to be internal calls and CreateThread was supposed to be the API function everyone would call. Another potential explanation is that MS has a long & glorious history of ignoring the standard & making very bad decisions about naming thing...
Python circular importing?
... specific to your case: Try changing entities/post.py to do import physics and then refer to physics.PostBody rather than just PostBody directly. Similarly, change physics.py to do import entities.post and then use entities.post.Post rather than just Post.
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Replace console output in Python
...
An easy solution is just writing "\r" before the string and not adding a newline; if the string never gets shorter this is sufficient...
sys.stdout.write("\rDoing thing %i" % i)
sys.stdout.flush()
Slightly more sophisticated is a progress bar... this is something I am using:
d...
NUnit vs. Visual Studio 2008's test projects for unit testing [closed]
I am going to be starting up a new project at work and want to get into unit testing. We will be using Visual Studio 2008, C#, and the ASP.NET MVC stuff. I am looking at using either NUnit or the built-in test projects that Visual Studio 2008 has, but I am open to researching other suggestions. ...
How do you performance test JavaScript code?
...e user/client. For example, we had a project with an Ext accordion that expanded to show some data and then a few nested Ext grids. Everything was actually rendering pretty fast, no single operation took a long time, there was just a lot of information being rendered all at once, so it felt slow to...