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Defining a method in Ruby 2.x returns a symbol representing the name: class Example puts def hello end end #=> :hello This allows for interesting metaprogramming techniques. For instance, methods can be wrapped by other methods: class Class def logged(name) original_method...

You can use a For Each...Next loop to iterate through any IEnumerable type. This includes arrays, lists, and anything else that may be of type IEnumerable or returns an IEnumerable. An example of looping through a DataTable's Rows property would look like this: For Each row As DataRow In DataTable...

Dependencies npm i -D webpack babel-loader webpack.config.js const path = require('path'); module.exports = { entry: { app: ['babel-polyfill', './src/'], }, output: { path: __dirname, filename: './dist/[name].js', }, resolve: { extensions: ['', '.js'], }...

Required modules npm install --save-dev webpack extract-text-webpack-plugin file-loader css-loader style-loader Folder structure . └── assets    ├── css     ├── images    └── js webpack.config.js const webpack = require('webpack'); const ExtractTextPlugin = require('extract-text-webp...

An overload without conversions needed for parameter types or only conversions needed between types that are still considered exact matches is preferred over an overload that requires other conversions in order to call. void f(int x); void f(double x); f(42); // calls f(int) When an argument b...

Let's suppose we have a reference to the JQuery type definition and we want to extend it to have additional functions from a plugin we included and which doesn't have an official type definition. We can easily extend it by declaring functions added by plugin in a separate interface declaration with ...

If you only want to execute a single statement, you can use the engine directly and it will open and close the connection for you: result = engine.execute('SELECT price FROM products') for row in result: print('Price:', row['price'])

A hexadecimal number is a value in base-16. There are 16 digits, 0-9 and the letters A-F (case does not matter). A-F represent 10-16. An octal number is a value in base-8, and uses the digits 0-7. A binary number is a value in base-2, and uses the digits 0 and 1. All of these numbers result in ...

When an extension method returns a value that has the same type as its this argument, it can be used to "chain" one or more method calls with a compatible signature. This can be useful for sealed and/or primitive types, and allows the creation of so-called "fluent" APIs if the me...

import flash.net.URLRequest; import flash.media.Sound; import flash.events.Event; var req:URLRequest = new URLRequest("click.mp3"); var snd:Sound = new Sound(req); snd.addEventListener(Event.COMPLETE, function(e: Event) { snd.play(); }

Elm has a special syntax for lambda expressions or anonymous functions: \arguments -> returnedValue For example, as seen in List.filter: > List.filter (\num -> num > 1) [1,2,3] [2,3] : List number More to the depth, a backward slash, \, is used to mark the beginning of lambda ex...

It is very convenient to use extension methods with interfaces as implementation can be stored outside of class and all it takes to add some functionality to class is to decorate class with interface. public interface IInterface { string Do() } public static class ExtensionMethods{ pu...

Ruby will need to be installed first before setup. You can install Ruby through the apt package manager, rbenv, or rvm. Then Run sudo su -c "gem install sass"

Usually authentication&authorization processes are performed by built-in cookie and token supports in .net MVC. But if you decide to do it yourself with Session you can use below logic for both page requests and ajax requests. public class SessionControl : ActionFilterAttribute { public o...

arr = np.arange(7) print(arr) # Out: array([0, 1, 2, 3, 4, 5, 6]) Comparison with a scalar returns a boolean array: arr > 4 # Out: array([False, False, False, False, False, True, True], dtype=bool) This array can be used in indexing to select only the numbers greater than 4: arr[arr&...

You can open several content managers at the same time: with open(input_path) as input_file, open(output_path, 'w') as output_file: # do something with both files. # e.g. copy the contents of input_file into output_file for line in input_file: output_file.write(line...

Install the necessary Python Library via: $ pip install elasticsearch Connect to Elasticsearch, Create a Document (e.g. data entry) and "Index" the document using Elasticsearch. from datetime import datetime from elasticsearch import Elasticsearch # Connect to Elasticsearch using ...

One can select rows and columns of a dataframe using boolean arrays. import pandas as pd import numpy as np np.random.seed(5) df = pd.DataFrame(np.random.randint(100, size=(5, 5)), columns = list("ABCDE"), index = ["R" + str(i) for i in range(5)]) print (...

Doxygen is a commonly used code documentation tool (for languages including C++, C# and Java) that also supports the use of Markdown. In addition to the standard Markdown syntax, there are a number of Doxygen-specific elements. The primary features are the use of @ref tags for references, and the @...

In order to install PostgreSQL on OSX, you need to know which versions are currently supported. Use this command to see what versions you have available. sudo port list | grep "^postgresql[[:digit:]]\{2\}[[:space:]]" You should get a list that looks something like the following: post...