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In javascript, is an empty string always false as a boolean?
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Yes. Javascript is a dialect of ECMAScript, and ECMAScript language specification clearly defines this behavior:
ToBoolean
The result is false if the argument is the empty String (its length is zero);
otherwise the result is true
Quote taken from http://www.ecma-inte...
what is “strict mode” and how is it used?
...en looking over the JavaScript reference on the Mozilla Developer Network, and I came across something called "strict mode" . I read it over and I'm having trouble understanding what it does. Can someone briefly explain (in general) what its purpose is and how it is useful?
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How to complete a git clone for a big project on an unstable connection?
...codebase, but at the moment I have an internet connection of about 300kbps and it's just anything but stable. I can get the connection back any moment, but then the git clone process already stopped working, and no way to get it running again. Is there some way to have a more failure-resistant git c...
“Could not find any information for class named ViewController”
...roject.
Steps:
In the project file explorer (left panel) find the class and right click -> Delete
Remove reference (do not move to trash as you will lose the class for good)
Right click on the folder that contained the class -> Add files to ...
Find the class you just deleted in the file sy...
WebKit issues with event.layerX and event.layerY
... deprecation warning on an event (at least in my opinion). One mousemove handler and your console explodes. :)
Here's a recent jQuery ticket: http://bugs.jquery.com/ticket/10531
UPDATE: This is fixed now if you upgrade to jQuery 1.7.
Please note that if upgrading jQuery doesn't fix the issue for...
std::function vs template
...ew additions. The most popular is that they are horribly slow. I tested it and they truly suck in comparison with templates.
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What are the obj and bin folders (created by Visual Studio) used for?
I created a new project in Visual Studio 2010 and noticed that there are now two new folders named obj and bin in my project directory.
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What is the smallest possible valid PDF?
...oy. Acrobat opens it, but it complains somewhat. There is one page in it and it is 3/72" square, the minimum allowed by the spec.
However, Acrobat X doesn't even bother with the cross reference table anymore, so we can take that out:
%PDF-1.0
1 0 obj<</Type/Catalog/Pages 2 0 R>>endo...
Python != operation vs “is not”
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== is an equality test. It checks whether the right hand side and the left hand side are equal objects (according to their __eq__ or __cmp__ methods.)
is is an identity test. It checks whether the right hand side and the left hand side are the very same object. No methodcalls ...
Global and local variables in R
I am a newbie for R, and I am quite confused with the usage of local and global variables in R.
3 Answers
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