1. Use var:
var a = [];
for (var i = 0; i < 10; iPP) {
a[i] = function () {
console.log(i);
};
}
a[6](); // 10
2. Use let
var a = [];
for (let i = 0; i < 10; iPP) {
a[i] = function () {
console.log(i);
};
}
a[6](); // 6
question: in 1, the I in the console.log (i), inside the function assigned to the array an in the loop points to the global I, doesn"t the I of a [I] also point to the global I, and only a [10] has value?
this question should not be related to closures. You should understand the scope of var and let.
take a look at the following example, and you'll see.
//
let cons = (car,cdr) => (k)=> k === 1 ? car : cdr
let car = (cons) => cons(1)
let cdr = (cons) => cons(2)
//
var cons2 = cons('2', '')
var cons1 = cons('1', cons2)
console.log(cdr(cdr(cons1))) // Previous: How can google map dynamically draw tracks of different colors? Where should the timer be added?
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