Tree shaking while bundling

Is it possible anyhow to implement tree shaking during bundling.

Suppose I have a file say greetings.js:

export const sayHi = (name) => {return `Jarvis says hi to ${name}`};
export const sayBye = (name) => {return `Jarvis says bye to ${name}`};

Now if in my project I am only using sayHi then I want sayBye to be removed from the final bundle which is currently not the case. Is it possible anyhow to implement this (even if I had to do changes in the config file for the metro bundler).

[neiker]

Its february 2020, brexit happened but not this.

[cpojer]

@rafeca and @mjesun have since left Facebook. We are not actively working on tree shaking at Facebook and are exploring other more promising ways to keep our app size small.

If you are using Metro for React Native, it is unlikely that tree shaking will have a major impact on your applications size or behavior. If you are looking for size improvements, consider compressing the JS bundle that you ship with your app. If you are looking for performance improvements, there are likely many other things (like shipping Hermes and bytecode) that will have a large impact.

I’ll close this as wontfix now but we will accept contributions towards tree shaking – and I’m accepting your job applications if you wanna work on this kinda stuff at Facebook London 😃