Tutorial by Examples: od

The Memory Model is difficult to understand, and difficult to apply. It is useful if you need to reason about the correctness of multi-threaded code, but you do not want to have to do this reasoning for every multi-threaded application that you write. If you adopt the following principals when wri...

Use an ensure clause if there is code you always want to execute. def divide(x, y) begin z = x/y return z rescue ZeroDivisionError puts "Don't divide by zero!" rescue TypeError puts "Division only works on numbers!" return nil rescue => e ...

There are three ways to quote something using a Julia function: julia> QuoteNode(:x) :(:x) julia> Meta.quot(:x) :(:x) julia> Expr(:quote, :x) :(:x) What does "quoting" mean, and what is it good for? Quoting allows us to protect expressions from being interpreted as sp...

Method overriding is the way of using polymorphism between classes. if one class is inherited from another, the former (sub class) can override the latter's (super class's) methods, and change the implementation. this is used where the super class defines the more general implementation of the meth...

One drawback of creating private method in Javascript is memory-inefficient because a copy of the private method will be created every time a new instance is created. See this simple example. function contact(first, last) { this.firstName = first; this.lastName = last; this.mobile; ...

LINQ extension methods on IEnumerable<T> take actual methods1, whether anonymous methods: //C# Func<int,bool> fn = x => x > 3; var list = new List<int>() {1,2,3,4,5,6}; var query = list.Where(fn); 'VB.NET Dim fn = Function(x As Integer) x > 3 Dim list = New List F...

$url1 = [uri]::EscapeDataString("http://test.com?test=my value") # url1: http%3A%2F%2Ftest.com%3Ftest%3Dmy%20value $url2 = [uri]::EscapeUriString("http://test.com?test=my value") # url2: http://test.com?test=my%20value # HttpUtility requires at least .NET 1.1 to be instal...

Note: these examples use the variables created in the Quick Start: Encoding section above. # url1: http%3A%2F%2Ftest.com%3Ftest%3Dmy%20value [uri]::UnescapeDataString($url1) # Returns: http://test.com?test=my value # url2: http://test.com?test=my%20value [uri]::UnescapeDataString($url2) # Re...

$scheme = 'https' $url_format = '{0}://example.vertigion.com/foos?{1}' $qs_data = @{ 'foo1'='bar1'; 'foo2'= 'complex;/?:@&=+$, bar''"'; 'complex;/?:@&=+$, foo''"'='bar2'; } [System.Collections.ArrayList] $qs_array = @() foreach ($qs in $qs_data.GetEnumerator()...

$scheme = 'https' $url_format = '{0}://example.vertigion.com/foos?{1}' $qs_data = @{ 'foo1'='bar1'; 'foo2'= 'complex;/?:@&=+$, bar''"'; 'complex;/?:@&=+$, foo''"'='bar2'; } [System.Collections.ArrayList] $qs_array = @() foreach ($qs in $qs_data.GetEnumerator()...

Encoded with [uri]::EscapeDataString() First, we'll decode the URL and Query String encoded with [uri]::EscapeDataString() in the above example: https://example.vertigion.com/foos? foo2=complex%3B%2F%3F%3A%40%26%3D%2B%24%2C%20bar'%22& complex%3B%2F%3F%3A%40%26%3D%2B%24%2C%20foo'%22=bar2&am...

Encoded with [uri]::EscapeDataString() First, we'll decode the URL and Query String encoded with [uri]::EscapeDataString() in the above example: https://example.vertigion.com/foos? foo2=complex%3B%2F%3F%3A%40%26%3D%2B%24%2C%20bar'%22& complex%3B%2F%3F%3A%40%26%3D%2B%24%2C%20foo'%22=bar2&am...

List all the node versions installed nvm ls v4.5.0 v6.7.0 Run command using any node installed version nvm run 4.5.0 --version or nvm exec 4.5.0 node --version Running node v4.5.0 (npm v2.15.9) v4.5.0 nvm run 6.7.0 --version or nvm exec 6.7.0 node --version Running node v6.7.0...

roslaunch is an important tool that manages the start and stop of ROS nodes. It takes one or more "*.launch" files as arguments. For this example, I will refer to the following (as asked in this question), so how can we execute those commands consecutively & automatically : roscd ste...

Each control has a property DataBindings which is a list of System.Windows.Forms.Binding objects. The Add()-method has some overloads which enables you easily binding to the property of an object: textBox.DataBindings.Add( "Text", dataObj, "MyProperty" ); Note, that binding b...

The module keyword can be used to begin a module, which allows code to be organized and namespaced. Modules can define an external interface, typically consisting of exported symbols. To support this external interface, modules can have unexported internal functions and types not intended for public...

Typically, packages consist of one or more modules. As packages grow, it may be useful to organize the main module of the package into smaller modules. A common idiom is to define those modules as submodules of the main module: module RootModule module SubModule1 ... end module SubModul...

Installation via NodeJS is the recommended method. It is preferred because you can use it to build the files selecting just the components you want. Step 1: Install Node (Link) Step 2: Install Gulp globally ( -g ) on your computer npm install -g gulp Semantic UI uses Gulp to provide command ...

Class is the piece of code where we define the attributes and/or behaviors of an object. You can define variables, constants, methods and constructors to the object, inside the class. In another words, class is the blueprint of an object. Let's see a sample class in Java, which defines a (simple) C...

Object is the base module in the Object Oriented Programming (OOP). An Object can be a variable, data structure (like an array, map, etc), or even a function or method. In OOP, we model real world objects like animals, vehicles, etc. An object can be defined in a class, which can be defined as the ...