Using Lodash with Ionic 2

I just started my first Ionic 2 application and struggled with adding Lodash as dependency. Since TypeScript 2 adding npm dependencies should be that easy:

npm install --save @types/lodash

You don’t have to deal with other tools like typings anymore. However the next build failed with this transpile error:

[12:06:18] transpile started …
[12:06:44] typescript: node_modules/@types/lodash/index.d.ts, line: 11444
‘]’ expected.

The problem is that the current version of the declaration file expects TypeScript 2.1 whereas Ionic 2 is using TypeScript 2.0. You need to search for a matching version and install the correct one:

npm view @types/lodash # check the dist-tags
npm install --save --save-exact @types/lodash@ts2.0

Don’t forget the save-exact flag. Otherwise your coworkers will run in the same problem after fetching.