# Ring (programming language)

Ring is a dynamically typed, general-purpose programming language. It can be embedded in C/C++ projects, extended using C/C++ code or used as a standalone language. The supported programming paradigms are imperative, procedural, object-oriented, functional, meta, declarative using nested structures, and natural programming. The language is portable (Windows, Linux, macOS, Android, WebAssembly, etc.) and can be used to create console, GUI, web, game and mobile applications.

## History

In 2009, Mahmoud Samir Fayed created a minor domain-specific language called Supernova that focuses on User interface (UI) creation and uses some ideas related to Natural Language Programming, then he realized the need for a new language that is general-purpose and can increase the productivity of natural language creation. Ring aims to offer a language focused on helping the developer with building natural interfaces and declarative DSLs.

## Goals

The general goals behind Ring:
* Applications programming language.
* Productivity and developing high quality solutions that can scale.
* Small and flexible language that can be embedded in C/C++ projects.
* Simple language that can be used in education and introducing Compiler/VM concepts.
* General-Purpose language that can be used for creating domain-specific libraries, frameworks and tools.
* Practical language designed for creating the next version of the Programming Without Coding Technology software.

## Examples
### Hello World program

The same program can be written using different styles. Here is an example of the standard "Hello, World!" program using four different styles.
The first style:
The second style:
The third style:
Another style: similar to xBase languages like Clipper and Visual FoxPro

### Change the keywords and operators

Ring supports changing the language keywords and operators.
This could be done many times in the same source file, and is useful for
* Translating the keywords from English to other human languages (Non-English-based programming languages)
* Customizing the language for use of a favorite style
* Porting Legacy code written in other languages
Translate Ring keywords to Japanese
Translate Ring keywords to Arabic
Use style similar to the Pascal programming language

### Loop command

The Loop command can take an integer to apply the continue semantics to enclosing outer loops

### Object-oriented programming

Ring supports object-oriented programming (classes, objects, composition, inheritance, encapsulation, etc.)
In Ring classes can be defined at runtime using the Eval function

## Implementation
### Compiler and virtual machine

Ring programs are not interpreted directly from the textual Ring file, but are compiled into bytecode, which is then run on the Ring virtual machine. The compilation process is typically invisible to the user and is performed at run-time, but it can be done offline in order to increase loading performance or reduce the memory footprint of the host environment by leaving out the compiler.
The compiler and the virtual machine are designed using visual programming through the Programming Without Coding Technology software then the C code is generated.

### Extensions

The following are extensions that can be used immediately after the installation of the full installation version (with a file size of about 280 MB for Ring 1.12). Since these are officially provided and maintained on the Ring side, the users are not bothered by library dependencies that may cause problems in other languages, and there is a concern that they can not be used suddenly even if there are destructive language specification changes.
The extensions are implemented in approximately 500,000 lines of C and C++ code.
* RingAllegro (Allegro Game Library)
* RingConsoleColor (Text coloring library for command prompt or the terminal)
* RingCurl (CURL Library)
* RingFreeGLUT (FreeGLUT)
* RingInternet (Internet related library)
* RingLibUV (LibUV-asynchronous I / O library)
* RingMurMurHash (Hash Function Library)
* RingMySQL (MySQL)
* RingODBC (Open Database Connectivity)
* RingOpenGL (OpenGL 1.1-4.6)
* RingOpenSSL (OpenSSL)
* RingPostgreSQL (PostgreSQL)
* RingQt (Qt framework)
* RingRayLib (raylib)
* RingSDL (SDL-Simple DirectMedia Layer Library)
* RingSQLite (SQLite)
* RingWinAPI (Windows API)
* RingWinCREG (Windows Registry)
* RingZIP (zip file processing library)

### Libraries

Ring comes with libraries written in Ring itself, such as libraries related to web and game development.
| Library Name | Description |
| Standard Library | General Classes and functions. |
| GUI Library | Classes and functions for creating GUI applications |
| Objects Library | Classes and functions for creating GUI applications using the MVC design pattern |
| Web Library | Simple framework for developing web applications using the MVC design pattern |
| Game Engine | Support developing 2D Games for Desktop and Mobile using Declarative Programming based on Allegro and LibSDL |
| Natural Library | General-Purpose Natural Language Programming Library. |
| Trace Library | A library for debugging applications. |
| Type Hints | A library for adding type hints to functions. |
| Big Number Library | Support arithmetic operations on huge numbers. |
| Fox Ring Library | Contains functions similar to Visual FoxPro. |
| ZeroLib Library | Contains classes where the Index starts from 0 instead of 1. |

### Applications

Ring is distributed with over 60 applications written in the language.
Some of these applications are
* Analog Clock application
* Calculator application
* The Checkers Game
* The Chess Game
* Fifteen Puzzle 3D Game
* Game 2048
* Knight Tour Game
* Minesweeper Game
* Othello Game
* Sokoban Game
* Sudoku Game
* Tic-tac-toe 3D Game
* Video Music Player application
* Windows Startup Manager application

### Tools

Ring is distributed with a Standard IDE that includes the following tools:
* Ring REPL (Read–eval–print loop)
* Ring2EXE (Distributing executable applications)
* RingPM (The Ring Package manager)
* Ring Notepad (Source-code editor)
* Form Designer (WYSIWYG GUI designer)
Ring is also distributed with extensions for many code editors such as Emacs, Notepad++, Geany, Atom, Sublime Text 2, and Visual Studio Code.

### Documentation

Ring is distributed with documentation written using Sphinx. A Japanese translation of the documentation is also available.

## Reception
### Popularity

Ring had a rapid rise and fall in popularity as measured by the TIOBE Programming Community Index. In February 2018, Ring broke into the top 50 for the first time (position 45). As of October 2020, Ring holds position 93 on the TIOBE index. Ring is listed by GitHub in the list of programming languages that are actively developed.

### Criticism

Ring critics pointed to some features in Ring that are not common in widely used programming languages.
* The list index starts from 1 instead of 0 (See: Zero-based numbering)
* Implicit type conversions (See: Implicit type conversions and "type punning")

#### The list index starts from 1 instead of 0

In Ring, the index of the first item in lists and the first character in strings is 1.

#### Implicit type conversions

The language can automatically convert between numbers and strings.