Playground is not supporting for "wrong order" classes

Actual behavior:

I write two classes in the playground and when I run the code I get an error in the console which land on the extend function.

class Snake extends Greeter {
constructor() {
super();
}
skip(){}
}
class Greeter {
constructor() {}

skip(){
    console.log('nothig to skip');
    this.preEnd();
    console.log('so just ended');
}
preEnd(){}

}

Expected behavior:

The order of the class should not matter.

Unlike functions, a class isn't actually created until its class declaration is reached, so it can't be forward referenced.

This is correct. Classes need to be declared before they are referenced on their value side.

This will now issue an error in cases where we can tell it's guaranteed not to work

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