Split empty string should return empty array

Question

If I use

''.split(',')

I get [''] instead of an empty array [].

How do I make sure that an empty string always returns me an empty array?

• Dave Newton: Write your own split replacement and break compatibility? If you split a non-empty string on ',' you get back an array with the original string in it, just like here.

Answer 1

Just do a simple check if the string is falsy before calling split:

function returnArr(str){
 return !str ? [] : str.split(',')
}
returnArr('1,2,3')
// ['1','2','3']
returnArr('')
//[]

• mortensen: But I still want 'p,q,r'.split(',').splice() to split into an array of 3 elements
• Dave Newton: Would break if you actually had a non-empty string, though; this seems like a special case that would be more easily handled by just checking for an empty string.
• Vibhu: This really doesn't answer the question. As @mortensen asked in this comment that 'p,q,r'.split(',').splice() will return an empty array [].

Answer 2

const arr = ''.split(',').filter(Boolean);
console.log('result:', arr)

• rjcarr: Clever, thanks!

Answer 3

try with this

 r=s?s.split(','):[];

• Dave Newton: I think you'd want the last s to be an empty array.
• Dave Newton: Then how did you have time to answer it?

Answer 4

I guess this should do it;

console.log(''.split(',').reduce((p,c) => c ? p.concat(c) : p ,[]));
console.log("test1,test2,".split(',').reduce((p,c) => c ? p.concat(c) : p ,[]));

Answer 5

Using condition ? exprIfTrue : exprIfFalse

https://developer.mozilla.org/en-US/docs/Web/JavaScript/Reference/Operators/Conditional_operator

let text1 = ''
let text2 = '1,2,3,4,5,6,7,8'
console.log(text1 == '' ? [] : text1.split(','));
console.log(text2 == '' ? [] : text2.split(','));

Answer 6

split() always splits into pieces (at least one) so you can try:

list=(!l)?[]:l.split(',');

Also you can write a new split method like:

String.prototype.split2 = function (ch) { 
 return (!this)?[]:this.split(ch) 
}

So tou can try:

''.split2(','); //result: []
'p,q,r'.split2(','); //result: ['p','q','r']