Typescript and webstorm, missing --module flag

Question

Editing a typescript project, that was created on VisualStudio, in WebStorm is replying this error:

Error:(1, 1) TS1148: Cannot compile external modules unless the '--module' flag is provided.

the code is simple like this:

in file Test.ts

class helloWorld{

}

export = helloWorld;

Thanks in advance for your help

EDITED

I forgot to mention that I was using a MAC.

Also after enter the post, on my quest to find the solution, I try to compile the web in VisualStudio Code for Mac, and I have the same problem there, that, make realize that the problem was not the IDE but something in common, that I didn't figure it out.

On fedemp answer this sentence trigger someting:

One is using the flag at compilation: tsc --module commonjs or --module amd.

So I go to Webstorm's Preferences -> Languages & Frameworks -> TypeScript and on the option "Command line options:" I added --module amd and done!