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| 在ES6之前:
let a = 1;
let b = 2;
let c = 3;
ES6可以這樣寫:
let [a, b, c] = [1, 2, 3];
let [foo, [[bar], baz]] = [1, [[2], 3]];
foo // 1
bar // 2
baz // 3
let [ , , third] = ["foo", "bar", "baz"];
third // "baz"
let [x, , y] = [1, 2, 3];
x // 1
y // 3
let [head, ...tail] = [1, 2, 3, 4];
head // 1
tail // [2, 3, 4]
let [x, y, ...z] = ['a'];
x // "a"
y // undefined
z // []
Destructuration 失敗example:
let [foo] = [];
let [bar, foo] = [1];
Output:foo : undefined
不完全Destructuration example:
let [x, y] = [1, 2, 3];
x // 1
y // 2
let [a, [b], d] = [1, [2, 3], 4];
a // 1
b // 2
d // 4
若=左邊是array，但=右邊不是array，則會error
//error
let [foo] = 1;
let [foo] = false;
let [foo] = NaN;
let [foo] = undefined;
let [foo] = null;
let [foo] = {};
Set也可以使用array Destructuration:
let [x, y, z] = new Set(['a', 'b', 'c']);
x // "a"
|