将对象转换为数组的优雅方式

Question

Let's say I have a function that returns either an array or a value:

const a = f(...);
// a === [ 1 ];

const b = f(...);
// b = 1;

What is the most elegant way to transform the returned value into an array, so that a === b ?

I was hoping something like [ ...b ] would work, but it throws. The solution I have come to so far is Array.isArray(b) ? b : [ b ] Array.isArray(b) ? b : [ b ] , but I'm curious if there's a cleaner way to do this, preferably a single function/non-branching expression

Answer 1

你可以做

return [b].flat()

Answer 2

The function Array.prototype.concat accepts either an array or a single value as a parameter.

This is assuming you want an array always .

 //This is just to illustrate. const f = (asArray) => asArray ? [1] : 1, a = [].concat(f(true)), b = [].concat(f(false)); console.log(a.length === b.length && a[0] === b[0]);

Answer 3

Perhaps a way out is to use the construct

Array.from()

Example:

Array.from(a());

and

Array.from(b());

Both should return you the result in an array.