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How can I make a div stick to the top of the screen once it's been scrolled to?
... for. I'd like the element to start at 200px below the top of the page (to allow room for other content) and then once the user has scrolled down become fixed at the top.
– evanr
Aug 1 '09 at 8:10
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Get to UIViewController from UIView?
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All this bs about "you shouldn't do this" is just that. If a view wants to know about its view controller, that is up to the programmer to decide. period.
– Daniel Kanaan
Dec 7 '15 at ...
How to prepend a string to a column value in MySQL?
I need a SQL update statement for updating a particular field of all the rows with a string "test" to be added in the front of the existing value.
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What does passport.session() middleware do?
...r/lib/strategies/session.js
Specifically lines 59-60:
var property = req._passport.instance._userProperty || 'user';
req[property] = user;
Where it essentially acts as a middleware and alters the value of the 'user' property in the req object to contain the deserialized identity of the user. To ...
is there a post render callback for Angular JS directive?
...s not a result of Angular but rather the browser. $timeout(fn) ultimately calls setTimeout(fn, 0) which has the effect interrupting the Javascript execution and allowing the browser to render the content first, before continuing the execution of that Javascript.
– parliament
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What is the “assert” function?
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assert will terminate the program (usually with a message quoting the assert statement) if its argument turns out to be false. It's commonly used during debugging to make the program fail more obviously if an unexpected condition occurs.
For example:
assert(len...
How to create a self-signed certificate for a domain name for development?
...poses. My web application solution contains a web API etc, that I need to call from external systems, hence I am not using localhost.
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What does “for” attribute do in HTML tag?
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The <label> tag allows you to click on the label, and it will be treated like clicking on the associated input element. There are two ways to create this association:
One way is to wrap the label element around the input element:
<label...
How do I create a custom iOS view class and instantiate multiple copies of it (in IB)?
... am currently making an app that will have multiple timers, which are basically all the same.
4 Answers
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What's the difference between Perl's backticks, system, and exec?
...It never returns true, because if the command is found it never returns at all.
There is also no point in returning STDOUT, STDERR or exit status of the command.
You can find documentation about it in perlfunc,
because it is a function.
system
executes a command and your Perl script is con...