Is it feasible to create a function in TypeScript that takes an array of strings and returns a string union?
Consider the following example function:
function myfn(strs: string[]) {
return strs[0];
}
If I use this function like:
myfn(['a', 'b', 'c']) // => return type is: 'a' | 'b' | 'c'
Can TypeScript handle this requirement?
To provide a description for the array item, you can add a generic parameter in TypeScript that will be inferred from the given value:
function findFirstElement<T extends string>(arr: T[]) {
return arr[0];
}
const result = findFirstElement(['apple', 'banana', 'cherry']) // 'apple' | 'banana' | 'cherry'
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