function Person(){}
var person = new Person();//Person
function fun(){
var index = 0;
//personsay
person.run = function(){
console.log(PPindex);//index
}
}
fun();//fun
//5personrun
for (var i = 0;i < 5;iPP) {
person.run();//12345
}
:funindexpersonrunindex
this is a closure.
when you add a function to person.run , the variable in function is not destroyed, even if it is a variable of an external function.
this is a closure.
gives you an address to learn:
https://developer.mozilla.org. https://developer.mozilla.org.
internal function, referencing the variables of the external function.
about closures: JavaScript scope and closure
references to the person.run function have not disappeared
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