Object.assign递归无法正常工作

Question

I have the following function:

 const test = (i, o) => { if (i < 1) return o else return Object.assign(o, test(i - 1, ({ value: i, label: i }))) } console.log(test(5, ({}))) 

And i except it to print:

[
    { value: '1', label: '1' },
    { value: '2', label: '2' },
    { value: '3', label: '3' },
    { value: '4', label: '4' },
    { value: '5', label: '5' }
]

However the result is:

{ value: 1, label: 1 }

What's wrong with recursive Object.assign?

Answer 1

The only way this could make sense is having an array as your result.

Here's a possible solution:

 function test(length) { return [...Array(length).keys()] .map(i => ({value: i + 1, label: i + 1})) } console.log(test(5)); 

Answer 2

如果要在此处递归：

 const test = (i, o) => (i ? test(i - 1, o) : []).concat(Object.assign({}, o, { value: i, label: i }));