How to return only one result using match() [duplicate]

I try to filter text using regular expressions

var regExpDouble = new RegExp(/[0-9]+([.,][0-9]{0,3})?/)
var someText = "0.33 mm"
var result = someText.match(regExpDouble)
console.log("match:", result)

I get result in output as array

match: [0.33,.33]

How to get only one result (first) without parsing array?