Tutorial by Examples: e

In Swift, memory management is done for you automatically using Automatic Reference Counting. (See Memory Management) Allocation is the process of reserving a spot in memory for an object, and in Swift understanding the performance of such requires some understanding of the heap and the stack. The h...

Assume we want to create a data type Person, which has a first and last name, an age, a phone number, a street, a zip code and a town. We could write data Person = Person String String Int Int String String String If we want now to get the phone number, we need to make a function getPhone :: P...

thinky is a lightweight node.js ORM for RethinkDB. First you need to have RethinkDB running on your server. Then install the thinky.io npm package into your project. npm install --save thinky Now import thinky into your model file. const thinky = require('thinky)(); const type = thinky.type ...

defmodule ATest do use ExUnit.Case [{1, 2, 3}, {10, 20, 40}, {100, 200, 300}] |> Enum.each(fn {a, b, c} -> test "#{a} + #{b} = #{c}" do assert unquote(a) + unquote(b) = unquote(c) end end) end Output: . 1) test 10 + 20 = 40 (Test.Test) t...

The ASP.NET Core RTM release introduced BundlerMinifier.Core, a new Bundling and Minification tool that can be easily integrated into existing ASP.NET Core applications and doesn't require any external extensions or script files. Using BundlerMinifier.Core To use this tool, simply add a reference ...

With ASP.NET Core the Microsoft team also introduced the Options pattern, which allows to have strong typed options and once configured the ability to inject the options into your services. First we start with a strong typed class, which will hold our configuration. public class MySettings { ...

This error occurs when tables are not adequately structured to handle the speedy lookup verification of Foreign Key (FK) requirements that the developer is mandating. CREATE TABLE `gtType` ( `type` char(2) NOT NULL, `description` varchar(1000) NOT NULL, PRIMARY KEY (`type`) ) ENGINE=InnoD...

If you need to add a property with a null value, you should use the predefined static final JSONObject.NULL and not the standard Java null reference. JSONObject.NULL is a sentinel value used to explicitly define a property with an empty value. JSONObject obj = new JSONObject(); obj.put("some...

Sometimes you may want to output something by one program and input it into another program, but can't use a standard pipe. ls -l | grep ".log" You could simply write to a temporary file: touch tempFile.txt ls -l > tempFile.txt grep ".log" < tempFile.txt This work...

While server side-code can run with elevated privileges, there is not an equivalent method to elevate privileges in client-side code (for obvious security reasons). As an alternative, you can specify credentials to emulate the access of a specific user or service account. To specify credentials, bu...

When testing for any of several equality comparisons: if a == 3 or b == 3 or c == 3: it is tempting to abbreviate this to if a or b or c == 3: # Wrong This is wrong; the or operator has lower precedence than ==, so the expression will be evaluated as if (a) or (b) or (c == 3):. The correct w...

Check existing remote git remote -v # origin https://github.com/username/repo.git (fetch) # origin https://github.com/usernam/repo.git (push) Changing repository URL git remote set-url origin https://github.com/username/repo2.git # Change the 'origin' remote's URL Verify new remote URL ...

ESLint is a code style linter and formatter for your style guide much like JSHint. ESLint merged with JSCS in April of 2016. ESLint does take more effort to set up than JSHint, but there are clear instructions on their website for getting started. A sample configuration for ESLint is as follows: {...

To define the struct called Person with an integer type variable age, integer type variable height and float type variable ageXHeight: struct Person { int age; int height; float ageXHeight; } Generally: struct structName { /+ values go here +/ }

As a good developer you have created following struct with both exported and unexported fields: type MyStruct struct { uuid string Name string } Example in Playground: https://play.golang.org/p/Zk94Il2ANZ Now you want to Marshal() this struct into valid JSON for storage in somet...

As of GHC 7.10, Applicative is a superclass of Monad (i.e., every type which is a Monad must also be an Applicative). All the methods of Applicative (pure, <*>) can be implemented in terms of methods of Monad (return, >>=). It is obvious that pure and return serve equivalent purposes, ...

BAD CODE Dim f As System.Windows.Forms.Form f.ShowModal() GOOD CODE Dim f As System.Windows.Forms.Form = New System.Windows.Forms.Form ' Dim f As New System.Windows.Forms.Form ' alternative syntax f.ShowModal() EVEN BETTER CODE (Ensure proper disposal of IDisposable object more info) Us...

Function TestFunction() As TestClass Return Nothing End Function BAD CODE TestFunction().TestMethod() GOOD CODE Dim x = TestFunction() If x IsNot Nothing Then x.TestMethod() 14.0 Null Conditional Operator TestFunction()?.TestMethod()

When we are using "width" with media queries it is important to set the meta tag correctly. Basic meta tag looks like this and it needs to be put inside the <head> tag. <meta name="viewport" content="width=device-width,initial-scale=1"> Why this is impo...

NLTK requires Python versions 2.7 or 3.4+. These instructions consider python version - 3.5 Mac/Unix : Install NLTK: run sudo pip install -U nltk Install Numpy (optional): run sudo pip install -U numpy Test installation: run python then type import nltk NOTE : For older versions of P...