Haml Article

Introduction

Haml is a templating system that is designed to avoid writing inline code in a web document and make the HTML cleaner. Haml gives the flexibility to have some dynamic content in HTML.

Haml stands for HTML Abstraction Markup Language. It was written in the programming langauge, Ruby by Hampton Caitlin with its initial release in 2006. Since then, a team works on developing Haml.

Features

There are four main principles of Haml:

User-friendly markup

It is easy to understand the language and ease of use too (implementation)

DRY

The Don't Repeat Yourself principle: Avoiding unecessary repititions and focusing on clean code.

Well-indented

The template allows for good indentation - This improves appearance as well as making it easy to read for readers and makes it easy to determine where a given element starts and ends.

Clear structure

Markup language with a clear structure will help in code maintenance and logical understanding of final result. It is unclear whether Haml offers any differential advantage in this regard.

Pros/Cons

Haml has its pros and cons:

Pros	Cons
Clean Syntax - By using indentation rather than closing tags and eliminating curly braces, Haml is fast to code vs normal HTML.	Whitespace sensitivity can be problematic. Haml uses indentation to defined structure, rather than closing tags. Though this, in most cases, makes code more efficient to write, it can also cause problems. Being off by one space can cause an error or change the structure of the code.
There are plenty of learning resources available for those who want to learn Haml. The documentation is detailed and well organized, and Haml is easy to pick up.	Bad Performance - The rendering time with Haml is slower than its competitors.
Clear Structure - Haml has a clear structure to its coding and indentation. This makes it easy to read and develop.	Steep(ish) learning curve - There is a slight learning curve for Haml in regards to being a newbie to HTML. Also once you learn Haml, switching between Haml and HTML will be a bit tedious as you will be used to fast syntax.

Extra Programs

Other templates / Markup languages: Markdown, ERB, Pug, Slim
Other front end technologies - CSS, HTML, JS, PHP
Front End JavaScript technologies and frameworks - ReactJS, AngularJS, Vue.js
Styling alternatives to CSS - Stylus, SASS, Less
Text Editors - Sublime, Notepad++
Other Front End web frameworks - Bootstrap, Foundation, Boilerplate

Sources

Summary

In conclusion:

Haml provides a nice alternative to HTML because it uses different ways in developing the markup for the front end of web pages. Usually, a developer would make a webpage which would include many HTML tags. These tags usually take up a lot of time (very mind numbing too) to produce. Haml solves this by allowing the developer to use the D.R.Y principle which utilises clean code and prevents mass copying of the same tags. You can see this in effect on websites like CodePen.