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Boolean(0) === false Boolean(0) will convert the number 0 into a boolean false. A shorter, but less clear, form: !!0 === false

To convert a string to boolean use Boolean(myString) or the shorter but less clear form !!myString All strings except the empty string (of length zero) are evaluated to true as booleans. Boolean('') === false // is true Boolean("") === false // is true Boolean('0') === fals...

If the values in a container have certain operators already overloaded, std::sort can be used with specialized functors to sort in either ascending or descending order: C++11 #include <vector> #include <algorithm> #include <functional> std::vector<int> v = {5,1,2,4,3};...

Managed resources are resources that the runtime's garbage collector is aware and under control of. There are many classes available in the BCL, for example, such as a SqlConnection that is a wrapper class for an unmanaged resource. These classes already implement the IDisposable interface -- it's u...

Iterating over List List<String> names = new ArrayList<>(Arrays.asList("Clementine", "Duran", "Mike")); Java SE 8 names.forEach(System.out::println); If we need parallelism use names.parallelStream().forEach(System.out::println); Java SE 5 fo...

class UsersController < ApplicationController def index hashmap_or_array = [{ name: "foo", email: "[email protected]" }] respond_to do |format| format.html { render html: "Hello World" } format.json { render json: hashmap_or_array } en...

class UsersController < ApplicationController def index respond_to do |format| format.html { render html: "Hello World" } end end end This is a basic controller, with the addition of the following route (in routes.rb): resources :users, only: [:index] Will...

resources :photos do member do get 'preview' end collection do get 'dashboard' end end This creates the following routes in addition to default 7 RESTful routes: get '/photos/:id/preview', to: 'photos#preview' get '/photos/dashboards', to: '...

git config --global merge.conflictstyle diff3 Sets the diff3 style as default: instead of the usual format in conflicted sections, showing the two files: <<<<<<< HEAD left ======= right >>>>>>> master it will include an additional section containi...

The following query returns the database options and metadata: select * from sys.databases WHERE name = 'MyDatabaseName';

parseFloat accepts a string as an argument which it converts to a float/ parseFloat("10.01") // = 10.01

// Generic types are declared using the <T> annotation struct GenericType<T> { pub item: T } enum QualityChecked<T> { Excellent(T), Good(T), // enum fields can be generics too Mediocre { product: T } }

// explicit type declaration let some_value: Option<u32> = Some(13); // implicit type declaration let some_other_value = Some(66);

Generic functions allow some or all of their arguments to be parameterised. fn convert_values<T, U>(input_value: T) -> Result<U, String> { // Try and convert the value. // Actual code will require bounds on the types T, U to be able to do something with them. } If the compi...

You can use curly braces to interpolate expressions into string literals: def f(x: String) = x + x val a = "A" s"${a}" // "A" s"${f(a)}" // "AA" Without the braces, scala would only interpolate the identifier after the $ (in this case f...

Description When working with a team who uses different operating systems (OS) across the project, sometimes you may run into trouble when dealing with line endings. Microsoft Windows When working on Microsoft Windows operating system (OS), the line endings are normally of form - carriage return ...

#include <stdio.h> /* The parameter name, apple, has function prototype scope. These names are not significant outside the prototype itself. This is demonstrated below. */ int test_function(int apple); int main(void) { int orange = 5; orange = test_function(oran...

A common use case for wanting to calculate the frame a label will take up is for sizing table view cells appropriately. The recommended way of doing this is using the NSString method boundingRectWithSize:options:attributes:context:. options takes String drawing options: NSStringDrawingUsesLineFr...

View jsFiddle: https://jsfiddle.net/HimmatChahal/jb5trg67/ Copy + Pasteable code below: <html> <body> <h1>This will fade in at 60 frames per second (or as close to possible as your hardware allows)</h1> <script> // Fad...

An enum is a set of logically related constants. Enum Size Small Medium Large End Enum Public Sub Order(shirtSize As Size) Select Case shirtSize Case Size.Small ' ... Case Size.Medium ' ... Case Size.Large ' ....