var o = {
a:11,
b: () => {
console.log("this is", this);
}
}
o.b(); 
Why does this point to window?
var o = {
a:11,
b: () => {
console.log("this is", this);
}
}
o.b();
Why does this point to window?
() => { }thisthis arrow function () = >
function is the object in which it is defined, not the object in which it is used. The direction of the
this object is variable, but in the arrow function, it is fixed.
the arrow function this points to the superior, o defines that all this points to window
without the arrow function this refers to o this object, o actually the this in the window.o, arrow function will indicate that the outer this, is the this, under window, of course it is window.
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