what does the inverse operation of rest parameters mean? what does
parameter sequence mean? What kind of data structure is it?
I want to know how the extension operator works
what does the inverse operation of rest parameters mean? what does
parameter sequence mean? What kind of data structure is it?
I want to know how the extension operator works
there is no principle, it's just grammatical candy. The former spread you already know, the latter can search for the keyword "deconstruction".
there are many articles about these two things, and here is only one example
var arr = [1, 2, 3];
function test(...args) {
console.log(args);
}
test(1, 2, 3);
// [ 1, 2, 3 ]
test(...arr);
// [ 1, 2, 3 ]
var [a, ...b] = arr;
// a = 1, b = [2, 3] function (.arr) {} to accept all the incoming things into the arr (the name is optional when you define it). Then the extension operator is the reverse process, spreading out the collected things again. Previous: How to count down the countdown to Synchronize for multiple clients
Next: What is the understanding of es6's extension operator?
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