Get Current Function Name In Strict Mode

In JavaScript, getting the current function name while running in strict mode can be a bit tricky, but fear not, as we have some tips to help you out. When running your code in strict mode, accessing Function.caller and Function.callee are restricted for security reasons. However, there is a way to achieve this by utilizing Error.stack.

One way to get the current function name in strict mode is by using the Error.stack property. When an error occurs in JavaScript, the Error object captures a stack trace, which includes information about the call stack at the point where the error was thrown. By leveraging the stack trace provided by Error, we can extract the current function name.

To demonstrate this, let's create a simple utility function that retrieves the current function name:

function getCurrentFunctionName() {
  try {
    throw new Error();
  } catch (error) {
    const stack = error.stack.split("n")[2].trim();
    const functionName = stack.match(/ats(.*?)s/)[1];
    return functionName;
  }
}

function exampleFunction() {
  const currentFunctionName = getCurrentFunctionName();
  console.log("Current Function Name:", currentFunctionName);
}

exampleFunction(); // Output: "exampleFunction"

In the code snippet above, the getCurrentFunctionName function is defined to retrieve the current function name. Within this function, we intentionally throw an Error and capture the stack trace using error.stack. By parsing the stack trace, we can extract the function name and return it.

It's important to note that the exact structure of the stack trace may vary depending on the JavaScript engine and environment in which your code is running. Therefore, it's recommended to test and verify the output in your specific setup.

By utilizing this approach, you can effectively obtain the name of the current function even when running in strict mode. This can be particularly useful for debugging and logging purposes, providing insights into the execution flow of your code.

Remember, while accessing the current function name through Error.stack is a workaround for strict mode restrictions, it's essential to use it judiciously and consider the impact on performance and maintainability of your code.

In conclusion, with the help of the Error object and stack trace manipulation, you can successfully retrieve the current function name in strict mode. By understanding this technique, you can enhance the visibility and traceability of your JavaScript functions.