How can I create a function in typescript that accepts either something or nothing as input?
I attempted the following:
interface TestFn {
(input: any | void): string
}
const operation: TestFn = (input) => 'result';
operation('some data'); // this works
operation(); // this will throw an error
Utilizing optional parameters is a great way to enhance your code:
interface OptionalParam {
(input?: any): string // <- don't forget about the optionality
}
const example: OptionalParam = (input) => 'success';
example('data'); // this line works perfectly
example(); // this line also runs smoothly
The parameter input is denoted with the ? symbol, indicating its optional nature. For more details on optional parameters, delve into the TypeScript documentation, specifically the section on Optional and Default Parameters.
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