Custom Typings - How To

[MCKRUZ]

Can someone please once and for all post how to do custom typings in Typescript 2.0+. I have seen multiple answers all over stackoverflow and other sites all of which are wrong. Can someone from the team please let me know what the deal is?

[mhegazy]

What do you mean by "Custom Typings"? what are you looking for specifically?

[MCKRUZ]

meaning that if I create a NPM library that isn't hosted in NPM but rather a private repo.

[MCKRUZ]

so it doesn't appear in the typings folder

[mhegazy]

is it a module?

[MCKRUZ]

Yes it is

[mhegazy]

so let's say you have your declaration file for the module in @private\module\index.d.ts. You can add a path mapping for it.

{
    "compilerOptions": {
        "baseUrl": "./",
        "paths":{
            "@private/*": ["types/@private/*"]
        }
    }
}

would this work?

[mhegazy]

The ideal case would be the use of typeRoots to inject the additional directory. but this needs #11137 to be fixed first.

[towertop]

@mhegazy

So what the "paths" options is designed for? That confuses me.

[mhegazy]

So what the "paths" options is designed for? That confuses me.

what are you trying to do?

[DanielRosenwasser]

@towertop The paths field is useful to align TypeScript's module resolution process with that of your module loader (e.g. AMD, System.js), or for adding custom declarations that exist outside of the standard resolution locations.

[weswigham]

Alternatively: Since your packages are private, write your own private @types/module-name package, then point npm at it via your package.json.

Its higher effort, but, IMO, a much neater solution than managing mappings within your tsconfig. Since your package is private, why not have a private package for its types?

[towertop]

Thanks @DanielRosenwasser , I got it.

@mhegazy I was confused which is preferred when "typeRoots" and "paths" both help to patch declarations for external module.