How to use Inline Conditional Statements In Javascript
Inline conditional statements offer a concise way to implement conditional return types within a generic function. This approach leverages JavaScript’s ternary operator to determine the return type based on specified conditions.
Example: The function getResult returns a number if the input is a string’s length, or false if the input is not a string. Results are logged for both string and non-string inputs.
function getResult<T>(input: T): T extends string ? number : boolean {
return typeof input === 'string' ?
(input.length as T extends string ? number : boolean) :
(false as T extends string ? number : boolean);
}
const result1 = getResult("w3wiki");
const result2 = getResult(10);
console.log(result1);
console.log(result2);
Output:
13
false
How to Implement a Generic Function with a Conditional Return Type ?
Implementing a generic function with a conditional return type involves creating a function that can accept multiple data types and return different types based on specified conditions. This allows for flexible behavior depending on inputs. The function’s return type may vary dynamically, enhancing its versatility and utility in handling diverse scenarios within a program or system. There are several ways to implement a generic function with conditional return types which are as follows:
Table of Content
- Using Conditional Types
- Using Type Switching
- Using Type Assertion
- Using Type Guards:
- Using Inline Conditional Statements