How to split a string using split() and get the separators?

Question

I would like to split the following string at each letter using String.prototype.split(/[a-zA-Z]/):

'M 10 10L 150 300'

The result:

[ "", " 10 10", " 150 300" ]

But I want to receive this:

[ "", "M 10 10", "L 150 300" ]

What is the fastest way to get that result using JavaScript?

This comes close: `input.split(/(?=[A-Za-z])/)` – Tim Biegeleisen Jan 04 '18 at 01:39 — Tim Biegeleisen, Jan 04 '18 at 01:39

Psidom · Accepted Answer · 2018-01-04T01:41:25.017

1

Try use match with /[a-zA-Z][^a-zA-Z]*/g to capture a letter and the following non letter characters:

let s = 'M 10 10L 150 300'

console.log(
  s.match(/^[^a-zA-Z]+|[a-zA-Z][^a-zA-Z]*/g)   // ^[^a-zA-Z]+ to include the case when 
                                               // the string doesn't begin with a letter
)

edited Jan 04 '18 at 01:41

answered Jan 04 '18 at 01:37

Psidom

209,562
33
339
356

This is missing the first empty string entry. – Tim Biegeleisen Jan 04 '18 at 01:41
@TimBiegeleisen Yeah. Not sure how critical it is. – Psidom Jan 04 '18 at 01:42
1

@Psidom, Not critical!!! :) – jak.b Jan 04 '18 at 01:48

How to split a string using split() and get the separators?

1 Answers1