Sass vs React

You are able to declare custom functions with Sass (for example, converting units) which can be easily invoked, even when using shorthand properties. This results in cleaner, more reusable code.

Sass allows you to nest selectors which results in code that is both faster to write and cleaner to read.

For example, this:

.parent 
  color: blue
  .child
    color: yellow

Will compile to this:

.parent {
  color: blue;
}
.parent .child {
  color: yellow;
}

Another big advantage for Sass is the very active community pushing the development forward at a rapid pace. Sass is constantly coming out with bug fixes, and are often the first to come out with improvements.

This is an important factor to keep in mind when picking a preprocessor to invest your time into.

It comes with two possible syntaxes:

• Sass - No parens or semicolons allowed and the nesting is dictated with whitespace.
• SCSS - SCSS syntax is a superset of CSS – which means SCSS can be written as CSS, but has been expanded to include the features of Sass as well.

SCSS is easier to pick up for beginners and Sass has a cleaner syntax. Having both syntaxes means you can pick the one that best suits your coding style.

The mandatory syntax rules for both SCSS and Sass results in a more consistent code. For a more detailed analysis between Sass and SCSS go here. To see a nice comparison of the Sass syntax against CSS and SCSS go here.

Sass simplifies minifying CSS files by offering a one-line command that will output a minified version.

It's very comfortable and easy to write/learn Sass, even for beginners.

Sass can be used with a framework called Compass, which provides additional functions and mixins which can reduce the amount of code you have to write.
For example, Compass will take care of vendor prefixes.

This:

div {
    background-image: -webkit-linear-gradient(#F00, #000);
    background-image: -moz-linear-gradient(#F00, #000);
    background-image: -o-linear-gradient(#F00, #000);
    background-image: linear-gradient(#F00, #000);
   }

Can be written as:

.gradient {
    @include background-image(linear-gradient(#F00, #000));
}

For a full list of features, check out the Compass documentation.

Rather than being limited to editing the outputted CSS file in devtools, with source maps you are able to manipulate the original .scss file.

There is also a C/C++ port of the Sass CSS precompiler called Libsass that decouples Sass from Ruby. It is very fast, portable and easy to build and integrate with a variety of platforms and languages.

The latest implementation of Sass is written in Dart, and compiles to pure JS with no native code or external dependencies, means you no longer need Ruby or libSass.

Since it's written in Ruby, it's easier and faster to use with Ruby apps.

Since every single UI component is created independently in JavaScript, it becomes very easy to reuse them throughout your app without having to re-write them.

React is built by Facebook engineers initially to be used only for their inner projects especially to solve the problem of building large complex applications with constantly changing data.

React can render it's components and data server side, then it sends those components as HTML to the browser.

This ensures faster initial loading time and SEO friendliness out of the box, since it's indexed as any other static website by search engines.

Instead of relying on the DOM, React implements a virtual DOM from scratch, allowing it to calculate precisely what needs to be patched during the next screen refresh. This is orders of magnitude faster than fiddling with the DOM itself.

React's one-way data binding (or one-way data flow) means that it's easy to see where and how your UI is updated and where you need to make changes. It's also very easy to keep everything modular, fast and well-organized.

ReactJS can be used independently as the only library for building the front-end, or it can be used alongside JavaScript libraries such as jQuery, or even Angular.

React provides a template engine (JSX) which is easy to use. But it's not mandatory.

The framework is widely used in the industry.

Since React's virtual DOM system is implemented completely in JavaScript, it's very easy to write UI test cases.

React has an official Chrome Extension which is used as a developing and debugging tool. It can be used to quickly and painlessly debug your application or view the whole application structure as it's rendered.

Flux is a platform agnostic pattern which can technically be used with any application or programming language.

One of Flux' main features is that it enforces uni-directional data flow which means that views do not change the data directly.

With React this is useful because this way it's easier to understand an application as it starts getting more complicated. By having two-way data binding, lead to unpredictable changes, where changing one model's data would end up updating another model. By using the Flux architecture, this can be avoided.

Since React v0.15, SVG is fully supported. React supports all SVG attributes that are recognized by today's browsers.

React is just a view library, so you still have (almost) full control over how your app behaves.

Reagent, Om, Rum, etc.

React is used on one of the most visited websites on the planet, Facebook. With stellar results and with millions of people experiencing it every day.