Can a default arrow function be exported in TypeScript using only one line?

Question

Can a default arrow function be exported in TypeScript using only one line?

const myFunction: () => void = () => {
    console.log('I am able to export my function like this');
};

export default myFunction;

export default () => void = () => {
    console.log('I am unable to export my function like this (Parsing error: Expression expected.)');
};

As you can see from the code above, it is possible to declare and assign a function in different ways. However, the arrow function cannot be exported using the same syntax with the export default statement. Why is that?

Any insights or explanations would be greatly appreciated.

javascript typescript export

Answer 1

Answer №1

If you're trying to export something as default with a type annotation on the same line, it won't work. However, you can achieve a similar result by using a named export instead. For example:

export const func: () => void = () => {
        console.log('I CAN export my function in this way');
    };

When importing this function in another file, you would do so like this:

import {func} from 'path'

Alternatively, if you prefer to keep the function signature separate from the export statement, you can do it like this:

export default () => {
    console.log('I CAN export my function in this way')
}

Then, you can import it using a different name:

import bloopityBloop from 'path'

Answer 2

If you're trying to export something as default with a type annotation on the same line, it won't work. However, you can achieve a similar result by using a named export instead. For example:

export const func: () => void = () => {
        console.log('I CAN export my function in this way');
    };

When importing this function in another file, you would do so like this:

import {func} from 'path'

Alternatively, if you prefer to keep the function signature separate from the export statement, you can do it like this:

export default () => {
    console.log('I CAN export my function in this way')
}

Then, you can import it using a different name:

import bloopityBloop from 'path'

Answer 3

Answer №2

Yes, it is possible to export a default function and apply a type or interface all in one line.

export default (
  () => {
    console.log('I CAN export my function like this');
  }
) as () => void;

Answer 4

Yes, it is possible to export a default function and apply a type or interface all in one line.

export default (
  () => {
    console.log('I CAN export my function like this');
  }
) as () => void;

Can a default arrow function be exported in TypeScript using only one line?

Answer №1

Answer №2

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