when you look at the project code, you can also find that some of the statements in the function are wrapped in curly braces, but there seems to be no difference when you execute them. What"s the use of this?
function a(){
console.log("<<<<");
{
let b = "123";
console.log(b);
}
console.log(">>>");
}
//
<<<<
123
>>> isolation scope
this is giving the let variable a separate scope
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