Tutorial by Examples: g

To develop an application for iOS, you should start with an application called Xcode. There are other alternative tools you can use, but Xcode is Apple's official tool. Note, however, that it only runs on macOS. The latest official version is Xcode 8.3.3 with Xcode 9 (currently in beta) due to be re...

There are two ways to connect to a MySQL/MariaDB server, depending on your infrastructure. Standard (TCP/IP) connection $dsn = 'mysql:dbname=demo;host=server;port=3306;charset=utf8'; $connection = new \PDO($dsn, $username, $password); // throw exceptions, when SQL error is caused $connection-...

Lists can be created in multiple ways. The recommended way is to use a List literal: var vegetables = ['broccoli', 'cabbage']; The List constructor can be used as well: var fruits = new List(); If you prefer stronger typing, you can also supply a type parameter in one of the following ways:...

Sets can be created via the constructor: var ingredients = new Set(); ingredients.addAll(['gold', 'titanium', 'xenon']);

Maps can be created in multiple ways. Using the constructor, you can create a new map as follow: var searchTerms = new Map(); Types for the key and value can also be defined using generics: var nobleGases = new Map<int, String>(); var nobleGases = <int, String>{}; Maps can othe...

When working with multi-module projects, it is helpful to centralize dependencies in a single location rather than having them spread across many build files, especially for common libraries such as the Android support libraries and the Firebase libraries. One recommended way is to separate the Gra...

To print a listing of the Error Code descriptions to the Immediate Window, pass it to the Debug.Print function: Private Sub ListErrCodes() Debug.Print "List Error Code Descriptions" For i = 0 To 65535 e = Error(i) If e <> "Application-defined or obje...

First, some terminology: argument (actual parameter): the actual variable being passed to a function; parameter (formal parameter): the receiving variable that is used in a function. In Python, arguments are passed by assignment (as opposed to other languages, where arguments can be passed by...

In Haskell, it often makes sense not to bother with file handles at all, but simply read or write an entire file straight from disk to memory†, and do all the partitioning/processing of the text with the pure string data structure. This avoids mixing IO and program logic, which can greatly help avoi...

String#split splits a String into an Array, based on a delimiter. "alpha,beta".split(",") # => ["alpha", "beta"] An empty String results into an empty Array: "".split(",") # => [] A non-matching delimiter results in an Array...

Array#join joins an Array into a String, based on a delimiter: ["alpha", "beta"].join(",") # => "alpha,beta" The delimiter is optional, and defaults to an empty String. ["alpha", "beta"].join # => "alphabeta" An em...

The easiest way to create a multiline string is to just use multiple lines between quotation marks: address = "Four score and seven years ago our fathers brought forth on this continent, a new nation, conceived in Liberty, and dedicated to the proposition that all men are created equal.&quot...

virtualenv is a tool to build isolated Python environments. This program creates a folder which contains all the necessary executables to use the packages that a Python project would need. Installing the virtualenv tool This is only required once. The virtualenv program may be available through yo...

public class DatabaseHelper extends SQLiteOpenHelper { private static final String DATABASE_NAME = "Example.db"; private static final int DATABASE_VERSION = 3; // For all Primary Keys _id should be used as column name public static final String COLUMN_ID = "_id&q...

A struct can be used to bundle multiple return values: C++11 struct foo_return_type { int add; int sub; int mul; int div; }; foo_return_type foo(int a, int b) { return {a + b, a - b, a * b, a / b}; } auto calc = foo(5, 12); C++11 Instead of assignment to indi...

Just execute lsb_release -a. On Debian: $ lsb_release -a No LSB modules are available. Distributor ID: Debian Description: Debian GNU/Linux testing (stretch) Release: testing Codename: stretch On Ubuntu: $ lsb_release -a No LSB modules are available. Distributor ID: Ubun...

The most common way to create a Symbol object is by prefixing the string identifier with a colon: :a_symbol # => :a_symbol :a_symbol.class # => Symbol Here are some alternative ways to define a Symbol, in combination with a String literal: :"a_symbol" "a_symbol&quot...

Given a String: s = "something" there are several ways to convert it to a Symbol: s.to_sym # => :something :"#{s}" # => :something

Given a Symbol: s = :something The simplest way to convert it to a String is by using the Symbol#to_s method: s.to_s # => "something" Another way to do it is by using the Symbol#id2name method which is an alias for the Symbol#to_s method. But it's a method that is unique to the...

NSDictionary *inventory = @{ @"Mercedes-Benz SLK250" : @(13), @"BMW M3 Coupe" : @(self.BMWM3CoupeInventory.count), @"Last Updated" : @"Jul 21, 2016", @"Next Update" : self.nextInventoryUpdateString };