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What is the difference between null and undefined in JavaScript?
...ed
alert(typeof TestVar); //shows undefined
null is an assignment value. It can be assigned to a variable as a representation of no value:
var TestVar = null;
alert(TestVar); //shows null
alert(typeof TestVar); //shows object
From the preceding examples, it is clear that undefined and null are ...
How do you run JavaScript script through the Terminal?
...to run a C program make filename then ./ filename . How do you do this with .js files?
15 Answers
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What is the difference between pip and conda?
...ager for python packages. However, I saw the installation on IPython's website use conda to install IPython.
12 Answers
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SQLAlchemy: cascade delete
I must be missing something trivial with SQLAlchemy's cascade options because I cannot get a simple cascade delete to operate correctly -- if a parent element is a deleted, the children persist, with null foreign keys.
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How to write WinForms code that auto-scales to system font and dpi settings?
...t there that say "WinForms doesn't auto-scale to DPI/font settings well; switch to WPF." However, I think that is based on .NET 1.1; it appears they actually did a pretty good job of implementing auto-scaling in .NET 2.0. At least based on our research and testing so far. However, if some of you out...
How does Apple find dates, times and addresses in emails?
... email contains a date, time or location, the text becomes a hyperlink and it is possible to create an appointment or look at a map simply by tapping the link. It not only works for emails in English, but in other languages also. I love this feature and would like to understand how they do it.
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What was the strangest coding standard rule that you were forced to follow? [closed]
When I asked this question I got almost always a definite yes you should have coding standards.
112 Answers
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How to prevent robots from automatically filling up a form?
I'm trying to come up with a good enough anti-spamming mechanism to prevent automatically generated input. I've read that techniques like captcha, 1+1=? stuff work well, but they also present an extra step impeding the free quick use of the application (I'm not looking for anything like that please)...
UIButton inside a view that has a UITapGestureRecognizer
I have view with a UITapGestureRecognizer . So when I tap on the view another view appears above this view. This new view has three buttons. When I now press on one of these buttons I don't get the buttons action, I only get the tap gesture action. So I'm not able to use these buttons anymore. What...
Worth switching to zsh for casual use? [closed]
... in Mac OS X is bash , which I'm generally happy to be using. I just take it for granted. It would be really nice if it auto-completed more stuff , though, and I've heard good things about zsh in this regard. But I don't really have the inclination to spend hours fiddling with settings to improv...