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javascripttypescriptthisobject-literal

Typescript object literal "this" keyword

What's the expected behavior when using this inside a function in an object literal?

For example, let's say I have a type foo that only has a function named bar and no other property on it. But in the fooObj.bar method, I'm able to access this.baz (where baz is not a property on type foo) I see no error. Shouldn't typescript error out, as fooObj does not have baz on it?

type foo = {
    bar(): void;
}
var fooObj: foo = {
    bar: () => {
        // TS does not error out when I access this.baz
        console.log(this.baz);
    }
}
Solution

  • Setting the "noImplicitThis": true compiler option is how you would enable this functionality now. This pull request enabled typed this in object literals. Aleksey L originally suggested this compiler option in a comment on the question, but at the time it didn't function that way.