When Are JavaScript Functions Required to Return Values?

Does Netbeans Suggest That Every JavaScript Function Must Return a Value?

When using Netbeans to add comments to JavaScript functions, you may notice that it automatically adds "@returns {undefined}" even for functions that don't explicitly return anything. This behavior has raised concerns about whether JavaScript functions are required to return values.

No, JavaScript Functions Do Not Always Require Return Values

Contrary to Netbeans' suggestion, JavaScript functions are not obligated to return values. In fact, functions without explicit return statements default to returning undefined. Therefore, you can ignore or delete the "@returns {undefined}" comment portion.

The Role of Return Values

Despite the lack of explicit return requirements, JavaScript functions still need to communicate their completion to the runtime environment. This communication is facilitated by returning a value, which serves as a signal that the function has concluded its execution.

Implicit Return of Undefined

For functions without explicit return statements, the runtime engine implicitly returns undefined. This behavior is similar to C/ functions declared as void, which indicate no return value.

Consequences of Ignoring Return Values

Although JavaScript functions can be written to omit return values, it is common practice to handle them. Neglecting to process return values can lead to unexpected results, especially in asynchronous code where functions execute concurrently.

Conclusion

While Netbeans' behavior may imply that JavaScript functions must return values, it is not a strict requirement. Functions can function correctly without explicit return statements, defaulting to returning undefined. However, it is advisable to consider the implications of ignoring return values and handle them appropriately for efficient and reliable code execution.

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