Ceylon (programming language)

Ceylon was a special kind of computer language made to help people write and read programs more easily and safely. It was created by Red Hat and works on the Java virtual machine, so it can run on many different computers. You could also change Ceylon programs into JavaScript so they could run on websites.

This language focused on stopping programs from crashing by handling things like empty lists and missing values with care. It also tried to keep its rules simple and clear so programmers would not get confused. Ceylon offered strong tools and ways to organize code, which made it easier to build big projects.

The name “Ceylon” is a clever hint about Java because both Java and the country once called Ceylon are islands known for growing coffee and tea. In 2017, the people behind Ceylon gave it to the Eclipse Foundation to keep it going, but work on it slowed down and finally stopped in 2020. By April 2023, the Eclipse Foundation said they were done trying to keep Ceylon alive.

Language features

Ceylon is inspired by Java but adds many new features.

One special part of Ceylon is its type system. Unlike Java, Ceylon uses a type system made only of objects. This makes it more consistent. Ceylon lets you combine types in two ways: union types and intersection types. Union types, written A|B, let a variable be more than one type. For example, a function might accept either an integer or a string. Intersection types, written A&B, help understand how types change in different situations.

Ceylon also supports first class functions and higher order functions. This means you can treat functions like any other value. You can pass functions as arguments or return them from other functions.

Versions

Ceylon had many versions released over the years. Some of the versions include:

• M1 0.1 "Newton" (Dec 20 2011)
• M2 0.2 "Minitel" (Mar 2 2012)
• M3 0.3 "V2000" (Jun 21 2012)
• M3.1 0.3.1 "V2000" (Jul 6 2012)
• M4 0.4 "Analytical Engine" (Oct 29 2012)
• M5 0.5 "Nesa Pong" (Mar 13 2013)
• M6 0.6 "Virtual Boy" (Sep 23 2013)
• 1.0 beta "Virtual Boy" (Sep 24 2013)
• 1.0.0 "No More Mr Nice Guy" (Nov 13 2013)
• 1.1.0 "Ultimate Ship The Second" (Oct 09 2014)
• 1.2.0 "A Series of Unlikely Explanations" (Oct 28 2015)
• 1.2.1 "Irregular Apocalypse" (Feb 11 2016)
• 1.2.2 "Charming But Irrational" (Mar 11 2016)
• 1.3.0 "Total Internal Reflection" (Sep 19 2016)
• 1.3.1 "Now We Try It My Way" (Nov 22 2016)
• 1.3.2 "Smile Tolerantly" (Mar 02 2017)
• 1.3.3 "Contents May Differ" (Aug 21 2017)

License

Ceylon is available as free software. Most of it uses the Apache License, and some parts use the LGPL license. This means you can use and change the code freely, following these rules.