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What does `void 0` mean? [duplicate]
...
What does void 0 mean?
void[MDN] is a prefix keyword that takes one argument and always returns undefined.
Examples
void 0
void (0)
void "hello"
void (new Date())
//all will return undefined
What's the point of that?
It seems pretty useless, doesn't it? If it alw...
How does having a dynamic variable affect performance?
...namic used as a parameter or rather those lines with dynamic behavior/context(?)
Here's the deal.
For every expression in your program that is of dynamic type, the compiler emits code that generates a single "dynamic call site object" that represents the operation. So, for example, if you have:
...
What is the purpose of the single underscore “_” variable in Python?
..._ has 5 main conventional uses in Python:
To hold the result of the last executed expression(/statement) in an interactive
interpreter session. This precedent was set by the standard CPython
interpreter, and other interpreters have followed suit
As a general purpose "throwaway" variable name to ind...
get dictionary key by value
... lookup. You can do something like this:
var myKey = types.FirstOrDefault(x => x.Value == "one").Key;
If values are unique and are inserted less frequently than read, then create an inverse dictionary where values are keys and keys are values.
...
Why is transposing a matrix of 512x512 much slower than transposing a matrix of 513x513?
After conducting some experiments on square matrices of different sizes, a pattern came up. Invariably, transposing a matrix of size 2^n is slower than transposing one of size 2^n+1 . For small values of n , the difference is not major.
...
Recursive lambda functions in C++11
...may make more sense:
std::function<int(int,int)> sum;
sum = [term,next,&sum](int a, int b)->int {
if(a>b)
return 0;
else
return term(a) + sum(next(a),b);
};
Obviously, this wouldn't work with auto. Recursive lambda functions work perfectly well (at least they do in MSVC, ...
Get GPS location from the web browser
...ll the browser support for geolocation is pretty good, all major browsers except ie7 and ie8 (and opera mini). IE9 does the job but is the worst performer. Checkout caniuse.com:
http://caniuse.com/#search=geol
Also you need the approval of your user to access their location, so make sure you check...
How to deal with page breaks when printing a large HTML table
...t;
<html>
<head>
<meta http-equiv="Content-Type" content="text/html; charset=UTF-8">
<title>Test</title>
<style type="text/css">
table { page-break-inside:auto }
tr { page-break-inside:avoid; page-break-after:auto }
thead { display:table-header-grou...
Sending an HTTP POST request on iOS
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The following code describes a simple example using POST method.(How one can pass data by POST method)
Here, I describe how one can use of POST method.
1. Set post string with actual username and password.
NSString *post = [NSString stringWithFormat:@"User...
how to convert binary string to decimal?
...ic literals for integers, so if the binary string is immutable, as in the example code in the question, one could just type it in as it is with the prefix 0b or 0B:
var binary = 0b1101000; // code for 104
console.log(binary); // prints 104
...