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What, exactly, is needed for “margin: 0 auto;” to work?
I know that setting margin: 0 auto; on an element is used to centre it (left-right). However, I know that the element and its parent must meet certain criteria for the auto margin to work, and I can never seem to get the magic right.
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How can I detect if a selector returns null?
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My favourite is to extend jQuery with this tiny convenience:
$.fn.exists = function () {
return this.length !== 0;
}
Used like:
$("#notAnElement").exists();
More explicit than using length.
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How to use NSCache
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You use it the same way you would use NSMutableDictionary. The difference is that when NSCache detects excessive memory pressure (i.e. it's caching too many values) it will release some of those values to make room.
If you can recre...
Why does Ruby have both private and protected methods?
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protected methods can be called by any instance of the defining class or its subclasses.
private methods can be called only from within the calling object. You cannot access another instance's private methods directly.
Here is a quick practical example:
def compare_to(x)
self.some_method <...
How to enable local network users to access my WAMP sites?
...s from the PC running the server i.e. localhost or 127.0.0.1 or ::1
But as it is a full version of Apache all you need is a little knowledge of the server you are using.
The simple ( hammer to crack a nut ) way is to use the 'Put Online' wampmanager menu option.
left click wampmanager icon -> Put...
See my work log in jira
...ra. Currently jira shows work log for individual story / sub tasks. But is it possible to show the total amount of work logged in jira by individual developer.
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What platforms have something other than 8-bit char?
...hen, someone on SO points out that char (aka 'byte') isn't necessarily 8 bits .
12 Answers
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Can someone explain the traverse function in Haskell?
...o grok the traverse function from Data.Traversable . I am unable to see its point. Since I come from an imperative background, can someone please explain it to me in terms of an imperative loop? Pseudo-code would be much appreciated. Thanks.
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Best GWT widget library? [closed]
...se, see google article to know how to best design your client application with GWT: Building MVP apps
After, you can use any widget of these libraries (say a table, or a combobox, a datepicker, etc) and incorporate it to your project. Try to use extended components ONLY if you don't see a way to do...
How to programmatically get iOS status bar height
I know that currently the status bar (with the time, battery, and network connection) at the top of the iPhone/iPad is 20 pixels for non-retina screens and 40 pixels for retina screens, but to future proof my app I would like to be able to determine this without hard coding values. Is it possible to...