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Mofei Zhang
ccfd5ecd3e
Note that bailing out adds false positives for hoisted functions whose only references are within other functions. For example, this rewrite would be safe.
```js
// source program
function foo() {
return bar();
}
function bar() {
return 42;
}
// compiler output
let bar;
if (/* deps changed */) {
function foo() {
return bar();
}
bar = function bar() {
return 42;
}
}
```
These false positives are difficult to detect because any maybe-call of foo before the definition of bar would be invalid.
Instead of bailing out, we should rewrite hoisted function declarations to the following form.
```js
let bar$0;
if (/* deps changed */) {
// All references within the declaring memo block
// or before the function declaration should use
// the original identifier `bar`
function foo() {
return bar();
}
function bar() {
return 42;
}
bar$0 = bar;
}
// All references after the declaring memo block
// or after the function declaration should use
// the rewritten declaration `bar$0`
```
babel-plugin-react-compiler
React Compiler is a compiler that optimizes React applications, ensuring that only the minimal parts of components and hooks will re-render when state changes. The compiler also validates that components and hooks follow the Rules of React.
This package contains the React Compiler Babel plugin use in projects that make use of Babel. You can find instructions for using this plugin here: https://react.dev/learn/react-compiler