javascript - Point to an object's property in a timeout -

i have simple object this:

myobject.percentage =  2; bar = document.getelementbyid('the_div'); 

so have this:

function upgrade_bar(bar,percentage) { console.log(percentage);      bar._timer = settimeout(function () {             upgrade_bar(bar,percentage)         }, 10000); }  upgrade_bar(bar,myobject.percentage);  myobject.percentage = 4; //upgrade_bar still console.logs 2 instead of 4 

so whilst running, else percentage changing.

but inside upgrade_bar function still 2 started as.

i'm wondering if there way use pointer not pass value pass reference date?

javascript doesn't have pass-by-reference arguments.

what can pass object , reference property. and, regarding comments different properties, can add argument know use.

function upgrade_bar(bar, settings, key) {     key = key || 'percentage';     console.log(settings[key]);      bar._timer = settimeout(function () {         upgrade_bar(bar, settings, key);     }, 10000); }  upgrade_bar(bar, myobject, 'percentage');