Prefix Provider Indonesia in Javascript

parse.js

function parseOperator(phone) { 
    var OperatorPrefix = {
        telkomsel: ["0812","0813","0821","0822","0852","0853","0823","0851"],
        indosat: ["0814","0815","0816","0855","0856","0857","0858"],
        tri: ["0895","0896","0897","0898","0899"],
        smartfren: ["0881","0882","0883","0884","0885","0886","0887","0888","0889"],
        xl: ["0817","0818","0819","0859","0877","0878"],
        axis: ["0838","0831","0832","0833"],
        bolt: ["0999", "0998"]
    }
    
    if (phone.length > 13) return {
        operator: null
    }

    for (var name in OperatorPrefix) {
        var _operator = OperatorPrefix[name];
        
        for (var index in _operator) {
            if (phone.startsWith(_operator[index])) return {
                operator: name,
                prefix: _operator[index],
                phone: phone
            }
        }
    }
    
    return {
        operator: null
    }
}

var ops = parseOperator("08966778890");