TypeScript compiler cannot find name 'BigInt'

The BigInt type in the Stats.d.ts file causes TypeScript to throw a 2304 (cannot find name) error, so the compilation fails.

TypeScript 2.8.3 memfs 2.14.1

[mjfreem1]

@streamich @pizzafroide Thanks for your responses. I tried out both suggestions and ended up opting to just upgrade TypeScript. C’est la vie.

[pizzafroide]

You are right: BigInt support was added to TypeScript 3.2, and, unfortunately, they say:

we have no immediate plans to provide downleveling support

However, BigInt support was added to memfs before it was in TypeScript. To make it work, we needed to add BigInt definition ourselves (in bigint.d.ts file). This file is still there. Maybe it could be copied to lib directory at compile time so “old TypeScript” users could import it. @mjfreem1, in the meantime, you can add the following code in some file and import it before importing memfs:

type BigInt = number;
declare const BigInt: typeof Number;