knockout.js - ko.utils.stringStartsWith not working -

hi have following code in ko

<!-- ko if: ko.utils.stringstartswith($root.currency(), inr) --> 

but though when getting data inr not getting validated. can 1 me

it looks ko.utils.stringstartswith never meant used outside of knockout internals. can either implement per post on link:

var stringstartswith = function (string, startswith) {               string = string || "";     if (startswith.length > string.length)         return false;     return string.substring(0, startswith.length) === startswith; }; 

or perhaps switch using indexof instead:

<!-- ko if: $root.currency().indexof("inr") === 0 -->