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Do Async Functions Always Return Promises, Even Without Explicit Returns?
Do Async Functions Always Return Promises, Even Without Explicit Returns?
Dec 17, 2024 pm 09:48 PM
Implicit Return of Promises in Async Functions
Contrary to the assumption that async functions return the values of await expressions directly, they actually always return a promise. In cases where an explicit return statement is not present, the value to be returned is automatically wrapped in a promise. This holds true for all return values, including non-promises.
Example:
In this scenario, even though a number is returned, it is still encapsulated within a promise. This is evident when accessing the returned value through the then() method.
Other Cases:
- Functions with no return statements also implicitly return a promise for an undefined value.
- Async functions involving await expressions return a promise for the value returned from the await operation.
Exception:
An exception to this rule occurs when a promise is explicitly returned from within an async function. In such cases, the promise is not re-wrapped.
Example:
Conclusion:
While this behavior may deviate from traditional JavaScript return statements, it aligns with the concept of generators in ES6, which do not return the exact value as the return statement.
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