Why Do Native JavaScript Functions Display as \"Native Code\"?

Why Native JavaScript Functions Show as "Native Code"

When attempting to inspect the declarations of JavaScript native code in Chrome or Firefox, you may encounter the message "native code." This indicates that the functionality is implemented in C or C rather than JavaScript.

Understanding Native Code

Native code refers to code that is not interpreted by the JavaScript engine. Instead, it is compiled directly into machine code by the browser's rendering engine. This implementation is used for performance optimization, as native code can run much faster than interpreted JavaScript.

Dispelling Myths

Contrary to common belief, native JavaScript functions are not stored as JavaScript code within the browser. They are directly integrated into the browser's C or C codebase. Therefore, it is impossible to access the source code of these functions using traditional debugging tools.

Accessing Source Code

If you are curious about the actual implementation of native JavaScript functions, you can access the source code of the following repositories:

• Chromium: https://chromium.googlesource.com/
• Firefox: https://hg.mozilla.org/mozilla-central/

However, it should be noted that these source repositories are incredibly complex and may require a significant understanding of C or C programming to navigate and understand the implementation of native JavaScript functions.

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