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What do the different readystates in XMLHttpRequest mean, and how can I use them?
XMLHttpRequest has 5 readyState s, and I only use 1 of them (the last one, 4 ).
5 Answers
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Is SQL or even TSQL Turing Complete?
...e programming languages, so that's kinda cheating).
In this set of slides Andrew Gierth proves that with CTE and Windowing SQL is Turing Complete, by constructing a cyclic tag system, which has been proved to be Turing Complete. The CTE feature is the important part however -- it allows you to crea...
How can I create a two dimensional array in JavaScript?
I have been reading online and some places say it isn't possible, some say it is and then give an example and others refute the example, etc.
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is there an virtual environment for node.js?
...s is your main issue, then maybe consider using the very cool 'bundle' command with npm. This is closer to freezing gems or using bundler in rails, rather than rvm.
It's super easy. Just create a package.json file:
{ "name": "yourapp", "version": "0.0.1", "dependencies": {"jade": "0.4.1"}}
and t...
How to 'insert if not exists' in MySQL?
I started by googling, and found this article which talks about mutex tables.
10 Answers
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Logical Operators, || or OR?
... no "better" but the more common one is ||. They have different precedence and || would work like one would expect normally.
See also: Logical operators (the following example is taken from there):
// The result of the expression (false || true) is assigned to $e
// Acts like: ($e = (false || true...
Custom CSS Scrollbar for Firefox
...verflow.com/a/54101063/405015
https://stackoverflow.com/a/53739309/405015
And this for background info: https://bugzilla.mozilla.org/show_bug.cgi?id=1460109
There's no Firefox equivalent to ::-webkit-scrollbar and friends.
You'll have to stick with JavaScript.
Plenty of people would like this feat...
Math - mapping numbers
How do I map numbers, linearly, between a and b to go between c and d.
9 Answers
9
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How to center a subview of UIView
I have a UIView inside a UIView m and I want the inner UIView to be always centered inside the outer one, without it having to resize the width and height.
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Conditional HTML Attributes using Razor MVC3
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You didn't hear it from me, the PM for Razor, but in Razor 2 (Web Pages 2 and MVC 4) we'll have conditional attributes built into Razor(as of MVC 4 RC tested successfully), so you can just say things like this...
<input type="text" id="@strElementID" class="@strCSSClass" />
If strCSSClass ...