jquery - Datatables remove this !!~ it doesnt return -

regarding in sample

i dont understand whats use of !!~

this script in fiddle

$.fn.datatable.ext.search.push(    function(settings, data, dataindex) {       var tdvalues=[];       var $tds=table.row(dataindex).nodes().to$().find('td');       $tds.each(function(){          var $this=$(this);          var hasselect=$this.find('select').length >0; // check if current cell has select box          var curtdvalue= hasselect ? $this.find('option:selected').text() : $this.text();          tdvalues.push(curtdvalue);       });       var rowvalues=tdvalues.join(' ');       return !!~rowvalues.tolowercase().indexof(table.search().tolowercase()); //<---this area    }      ); 

if remove !!~ doesnt return. cant see in manual of datatables $.fn.datatable.ext.search.push cant see in manual.

edited

this answered tilde or ~ how this? $.fn.datatable.ext.search.push