Javascript Debounce Utilities

debouncer.js

// Implementation

// run key up event handler as debounced key down handlers
var 
  _debounceTimeout; // key debouncer required params

// Usage
debounceStart(function(){
	// Function which is to be debounced
});


/**
 *  Debounce Start Function 
 *  Only starting call will be executed ( in case successive function calls) 
 *  and rest of them will be ignored
 * 
 * wait depends on different event listeners --> for keydown event it works at around 450ms
 */
 
function debounceStart(func){
    var callNow = !_debounceTimeout;
    clearTimeout(_debounceTimeout);
    _debounceTimeout = setTimeout(function(){
    	_debounceTimeout = null;
    },450); //blank timer
    if(callNow)
      func.call(undefined);
}