What are some of the advantages/disadvantages of writing JavaScript code in a language that compiles to JavaScript?

Technology CommunityCategory: JavaScriptWhat are some of the advantages/disadvantages of writing JavaScript code in a language that compiles to JavaScript?
VietMX Staff asked 3 years ago

Some examples of languages that compile to JavaScript include CoffeeScript, Elm, ClojureScript, PureScript, and TypeScript.

Advantages:

  • Fixes some of the longstanding problems in JavaScript and discourages JavaScript anti-patterns.
  • Enables you to write shorter code, by providing some syntactic sugar on top of JavaScript, which I think ES5 lacks, but ES2015 is awesome.
  • Static types are awesome (in the case of TypeScript) for large projects that need to be maintained over time.

Disadvantages:

  • Require a build/compile process as browsers only run JavaScript and your code will need to be compiled into JavaScript before being served to browsers.
  • Debugging can be a pain if your source maps do not map nicely to your pre-compiled source.
  • Most developers are not familiar with these languages and will need to learn it. There’s a ramp up cost involved for your team if you use it for your projects.
  • Smaller community (depends on the language), which means resources, tutorials, libraries, and tooling would be harder to find.
  • IDE/editor support might be lacking.
  • These languages will always be behind the latest JavaScript standard.
  • Developers should be cognizant of what their code is being compiled to — because that is what would actually be running, and that is what matters in the end.

Practically, ES2015 has vastly improved JavaScript and made it much nicer to write. I don’t really see the need for CoffeeScript these days.