in es6. The extension operator expands the array
[1Magol 2pr 3] unfolds as 1Magol 2Jol 3, so what is this 1Magol 2Jol 3? An array is not an array, a string is not a string
later, there was also the operation of the object. The operator
is called deconstructing assignment?
let {x, y, .z} = {x: 1, y: 2, a: 3, b: 4};
assigns all the properties of the target object to the specified object?
makes the target object have this object attribute value?
when you look at something, you should click on it. It is wrong to use .arr alone.
array . extension operator
function demo (a, b) {
console.log(a, b)
}
demo(...[1, 2])// 1 2
demo([1, 2]) //[1, 2] undefined
// demo(arr[0], arr[1])
// what is deconstruction assignment
I believe you should understand this
let {a: a, b: b} = {a: 1, b: 2}
a // 1
b // 2
// {a, b} = {a: 1, b: 2}
// deconstruct the extension operator of assignments and objects
let { x, y, ...z } = { x: 1, y: 2, a: 3, b: 4 }
// xy
// ...za:3, b:4
// z`{a: 3, b: 4}`Previous: Es6 extension operator query
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