settimeout function is not working well

Hi people.

I have some troubles with the settimeout function.
I have made a switch that an action can happen only one in the time of an interval.
This cod is not specially meant for the espruino but i have tried this in the browser implemented in a website.
The code works pretty well but if i click repeatedly fast, then the code ignores the if condition.
Do i have made a mistake in this codeblock?

var delay = true;
function blogPostTimer(){
    if(delay == true){
        delay = false;
        postMessage();
    }else{
        setTimeout(function(){
        delay = true;
        }, 1000 * 5);
    }
}