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What is the difference between a weak reference and an unowned reference?
...from deallocating the referred object).
But why two keywords? This distinction has to do with the fact that Optional types are built-in the Swift language. Long story short about them: optional types offer memory safety (this works beautifully with Swift's constructor rules - which are strict in ord...
Why is Go so slow (compared to Java)?
...run fast themselves and produce code that's OK (there is a bit of optimisation). gccgo uses GCC's existing optimisation passes, and might provide a more pointful comparison with C, but gccgo isn't feature-complete yet.
Benchmark figures are almost entirely about quality of implementation. They don'...
Android splash screen image sizes to fit all devices
...in every drawable folder ( ldpi , mdpi , hdpi , and xhdpi ). My application is supposed to run good and beautiful on all phones and tablets. What sizes (in pixels) should I create so the splash displays nice on all screens?
...
What is the global interpreter lock (GIL) in CPython?
...iew this video or look at this set of slides. It might be too much information, but then you did ask for details :-)
Note that Python's GIL is only really an issue for CPython, the reference implementation. Jython and IronPython don't have a GIL. As a Python developer, you don't generally come acros...
What is the difference between Modal and Push segue in Storyboards?
...
A push Segue is adding another VC to the navigation stack. This assumes that VC that originates the push is part of the same navigation controller that the VC that is being added to the stack belongs to. Memory management is not an issue with navigation controllers and a...
Why is React's concept of Virtual DOM said to be more performant than dirty model checking?
... React: Rethinking best practices -- JSConf EU 2013 ) and the speaker mentioned that dirty-checking of the model can be slow. But isn't calculating the diff between virtual DOMs actually even less performant since the virtual DOM, in most of the cases, should be bigger than model?
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Drawing an SVG file on a HTML5 canvas
...ugs (but nightly has fixed them).
var img = new Image();
img.onload = function() {
ctx.drawImage(img, 0, 0);
}
img.src = "http://upload.wikimedia.org/wikipedia/commons/d/d2/Svg_example_square.svg";
Live example here. You should see a green square in the canvas. The second green square on the pa...
YouTube iframe API: how do I control an iframe player that's already in the HTML?
...
Fiddle Links: Source code - Preview - Small version
Update: This small function will only execute code in a single direction. If you want full support (eg event listeners / getters), have a look at Listening for Youtube Event in jQuery
As a result of a deep code analysis,...
Using varchar(MAX) vs TEXT on SQL Server
...acement for the TEXT datatype in SQL Server 2005 and Next SQL SERVER versions.
5 Answers
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Is there a CSS selector by class prefix?
...is picks up div elements whose class attribute meets either of these conditions:
[class^="status-"] — starts with "status-"
[class*=" status-"] — contains the substring "status-" occurring directly after a space character. Class names are separated by whitespace per the HTML spec, hence the si...