upgrading to TS4

[joaomilho]

The following code works fine on TS 3.4.5:

type Example = {
    eg: string;
};

const exampleDecoder: Decoder<Example> = object({
    eg: string,
});

In TS 4.0.3 however, I got this message:

Type 'Decoder<{ eg?: string; }, unknown>' is not assignable to type 'Decoder<Example, unknown>'.
  Type '{ eg?: string; }' is not assignable to type 'Example'.
    Property 'eg' is optional in type '{ eg?: string; }' but required in type 'Example'.ts(2322)

Any ideas?

[nvie]

I cannot replicate this behavior. I ran the following steps:

1. Create a new, empty, directory
2. yarn add typescript decoders
3. yarn run tsc --init
4. Create a test.ts file with the following content
5. Run yarn run tsc

This doesn't give any type errors for me.

[nvie]

Is there any additional information you can share?

[joaomilho]

Let me try.

[joaomilho]

Yeah, on an empty project it works fine here too. I'll take a look again and if I find anything I'll raise a new one. I guess we can close this one for now. Thanks for taking the time!

[joaomilho]

It's the strict option.