What is Elm ?
Elm is a pure functional programming language with a strong type system. It is Open Source (released under BSD-3-Clause license) and this year is 10 years old.
The current version is
0.19.1 and it is surrounded by an active community.
An example of compiler output:
naming error Line 44, Column 12 I cannot find a `Timestamp` type: 44| ts : Timestamp, ^^^^^^^^^ These names seem close though: Timstamp Time.Zone Task.Task Time.Month Hint: Read <https://elm-lang.org/0.19.1/imports> to see how `import` declarations work in Elm.
There is an online editor, named Ellie, to play with the language without the need to install anything on your machine. Ellie permits to install dependencies for your code, so you can prototype an entire project with it.
Applications in Elm follow the TEA (The Elm Architecture), an architectural pattern based on the following concepts:
- Model: the state of the application.
- View: transforms model into HTML code.
- Update: updates the model intercepting messages which came from the user interaction with the view.
Why Elm ?
To take practice with Elm I implemented a tiny project ts-converter: a browser extension to translate timestamps into human readable dates. Ts-converter is released as a libre software under GPLv3 license.