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Some attributes are directly accessible as properties of the element (e.g. alt, href, id, title and value). document.querySelector("a").href = "#top"; Other attributes, including data-attributes can be set as follows: document.querySelector("a").setAttribute("...

To remove an attribute, including directly accessible properties document.querySelector("a").removeAttribute("title"); Data attributes can also be removed as follows (modern browsers): // remove "data-foo" attribute delete document.querySelector("a").dat...

// Add observer let observer = NSNotificationCenter.defaultCenter().addObserverForName("nameOfTheNotification", object: nil, queue: nil) { (notification) in // Do operations with the notification in this block } // Remove observer NSNotificationCenter.defaultCenter().removeObser...

In its simplest form supported by all versions of bash, case statement executes the case that matches the pattern. ;; operator breaks after the first match, if any. #!/bin/bash var=1 case $var in 1) echo "Antartica" ;; 2) echo "Brazil" ;; 3) echo "Cat&qu...

4.0 Since bash 4.0, a new operator ;& was introduced which provides fall through mechanism. #!/bin/bash var=1 case $var in 1) echo "Antartica" ;& 2) echo "Brazil" ;& 3) echo "Cat" ;& esac Outputs: Antartica Brazil Cat ...

4.0 Since Bash 4.0, another operator ;;& was introduced which also provides fall through only if the patterns in subsequent case statement(s), if any, match. #!/bin/bash var=abc case $var in a*) echo "Antartica" ;;& xyz) echo "Brazil" ;;& *b*) ...

Quintile analysis is a common framework for evaluating the efficacy of security factors. What is a factor A factor is a method for scoring/ranking sets of securities. For a particular point in time and for a particular set of securities, a factor can be represented as a pandas series where the in...

This creates a variant (a tagged union) that can store either an int or a string. std::variant< int, std::string > var; We can store one of either type in it: var = "hello"s; And we can access the contents via std::visit: // Prints "hello\n": visit( [](auto&&a...

This is an advanced example. You can use variant for light weight type erasure. template<class F> struct pseudo_method { F f; // enable C++17 class type deduction: pseudo_method( F&& fin ):f(std::move(fin)) {} // Koenig lookup operator->*, as this is a pseudo-method...

This does not cover allocators. struct A {}; struct B { B()=default; B(B const&)=default; B(int){}; }; struct C { C()=delete; C(int) {}; C(C const&)=default; }; struct D { D( std::initializer_list<int> ) {}; D(D const&)=default; D()=default; }; std::variant<A,B> var_ab...

Lambda Expresions are an extension of anonymous methods that allow for implicitly typed parameters and return values. Their syntax is less verbose than anonymous methods and follows a functional programming style. using System; using System.Collections.Generic; using System.Linq; ...

Run go test as normal, yet with the coverprofile flag. Then use go tool to view the results as HTML. go test -coverprofile=c.out go tool cover -html=c.out

C99 C99 introduced the concept of designated initializers. These allow you to specify which elements of an array, structure or union are to be initialized by the values following. Designated initializers for array elements For a simple type like plain int: int array[] = { [4] = 29, [5] = 31, [1...

Calculating the factorial of a number is a classic example of a recursive function. Missing the Base Condition: #include <stdio.h> int factorial(int n) { return n * factorial(n - 1); } int main() { printf("Factorial %d = %d\n", 3, factorial(3)); return 0;...

With IpRateLimit middleware you can set multiple limits for different scenarios like allowing an IP or IP range to make a maximum number of calls in a time interval like per second, 15 minutes, etc. You can define these limits to address all requests made to an API or you can scope the limits to eac...

With ClientRateLimit middleware you can set multiple limits for different scenarios like allowing a Client to make a maximum number of calls in a time interval like per second, 15 minutes, etc. You can define these limits to address all requests made to an API or you can scope the limits to each URL...

8 The Object.values() method returns an array of a given object's own enumerable property values, in the same order as that provided by a for...in loop (the difference being that a for-in loop enumerates properties in the prototype chain as well). var obj = { 0: 'a', 1: 'b', 2: 'c' }; console.log...

Increment by var a = 9, b = 3; b += a; b will now be 12 This is functionally the same as b = b + a; Decrement by var a = 9, b = 3; b -= a; b will now be 6 This is functionally the same as b = b - a; Multiply by var a = 5, b = 3; b *= a; b will now...

Show curl version: curl --version GET a remote resource and have it displayed in the terminal: curl http://stackoverflow.com GET a remote resource and save it in a local file: curl -o file https://stackoverflow.com Add headers to response: curl -i http://stackoverflow.com Output only...

The original C standard had no intrinsic Boolean type, so bool, true and false had no inherent meaning and were often defined by programmers. Typically true would be defined as 1 and false would be defined as 0. C99 C99 adds the built-in type _Bool and the header <stdbool.h> which defines bo...