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What is a MIME type?
...of how it relates to browser plug-ins, as in what I need to know about it for building plug-ins, is provided, please explain in clear and simple words. What is it? Why do plug-ins have a MIME type?
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Swift and mutating struct
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The mutability attribute is marked on a storage (constant or variable), not a type. You can think struct has two modes: mutable and immutable. If you assign a struct value to an immutable storage (we call it let or constant in Swift) the value becomes immutable mode...
What values should I use for CFBundleVersion and CFBundleShortVersionString?
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Think of it this way: The "short version" (CFBundleShortVersionString) is the public version number. The "version" (CFBundleVersion) is more of an internal version number that could change far more frequently than the public "short version". Personally I...
How to prevent favicon.ico requests?
I don't have a favicon.ico, but my browser always makes a request for it.
11 Answers
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How do I find all files containing specific text on Linux?
I'm trying to find a way to scan my entire Linux system for all files containing a specific string of text. Just to clarify, I'm looking for text within the file, not in the file name.
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How do I check if a string is a number (float)?
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Which, not only is ugly and slow
I'd dispute both.
A regex or other string parsing method would be uglier and slower.
I'm not sure that anything much could be faster than the above. It calls the function and returns. Try/Catch doesn't introduce much overhead because the most com...
Difference between variable declaration syntaxes in Javascript (including global variables)?
...ually big ones.
There's a fourth way, and as of ES2015 (ES6) there's two more. I've added the fourth way at the end, but inserted the ES2015 ways after #1 (you'll see why), so we have:
var a = 0; // 1
let a = 0; // 1.1 (new with ES2015)
const a = 0; // 1.2 (new with ES2015)
a = 0; ...
When vectors are allocated, do they use memory on the heap or the stack?
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vector<Type> vect;
will allocate the vector, i.e. the header info, on the stack, but the elements on the free store ("heap").
vector<Type> *vect = new vector<Type>;
allocates everything on the free store.
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What does the 'static' keyword do in a class?
...static field exists[1] even if you create a million instances of the class or you don't create any. It will be shared by all instances.
Since static methods also do not belong to a specific instance, they can't refer to instance members. In the example given, main does not know which instance of th...
【转】用App Inventor 2实现电子围栏功能 - App应用开发 - 清泛IT社区，为创新赋能！
...相对复杂的部分，因此独立一章详细说明。
App Inventor自带地图组件，可以方便的实现电子围栏（地理围栏，Geofence）功能。
实现电子围栏需要的组件实现电子围栏需要用到地图Map容器，需要用到的组件有Map，类似画面，...