JS .splice不单独返回数组中已删除的项目

Question

Hopefully I can make sense with this.

Array.splice function returns an array containing all removed elements.

In my code, I'm only removing one element at a time but I need to store that removed item.

I'm doing this :

let toRem = $(this).closest("li");  

let temp = list.splice(toRem.index(), 1);
compList.push(temp[0]);
compList[compList.length - 1].completed = new Date;

toRem.remove();

Adding the temp array seems like such a waste but I can't see another way to do this. I understand if this is such a tiny thing that I shouldn't care about but I want to make this that much better if possible.

Answer 1

You should be able to combine the lines:

compList.push(list.splice(toRem.index(), 1)[0]);

Or if you don't want to do that, you could use destructuring:

let [temp] = list.splice(toRem.index(), 1);
compList.push(temp);

Answer 2

Well, this entirely depends on what you mean by better. There is readability, which is usually (but not always) being more verbose ie what you have now, and then there is making the code as short as you can.

If you have an issue with the temp variable, there is no need to use it:

compList.push(list.splice(toRem.index(), 1)[0]);

You could then improve upon this by making it less dependant on the size of the splice:

compList.push(...list.splice(toRem.index(), 1));

The .push can accept any number of inputs and the spread ( ... ) operater will split an array into an input per item in the array.

Or, if you know there is always only going to be one element spliced, you could combine all three lines:

compList.push({ ...list.splice(toRem.index(), 1)[0], completed: new Date() });

As you can see though, as each version gets shorter or 'better' in one way, it loses out on readability.