Why is \W meta character not working properly in this Javascript regex -

hello i'm having trouble understanding regex.

'^.*(?=.{8,})(?=.*[a-z])(?=.*[a-z])(?=.*[\d\w]).*$' 

it should match zxc!"#zxc123, in online js regex tester, when try in application working on, wont match that. seems require letter w, assume comes non-word selector \w.

so case is, works in online tester, not actual js.

i've set example on fiddle, can see yourself.

$(document).ready(function(){      var inputfield = $('#regex');            inputfield.on('input', function(e){          var inputvalue = $(e.currenttarget).val();                    matchstring(inputvalue);      });              function matchstring(str){          var matches = str.match('^.*(?=.{8,})(?=.*[a-z])(?=.*[a-z])(?=.*[\d\w]).*$');                    if(matches){              $('#output').text('matches')          }          else{              $('#output').text('not matching')          }        }            matchstring(inputfield.val());  });

<script src="https://ajax.googleapis.com/ajax/libs/jquery/2.1.1/jquery.min.js"></script>  <input type="text" id="regex" value='zxc!"#zxc!"#'/>  <p id="output"></p>

i've tested regex on regex101

i hope explanation, because seems odd me. in advance

it because syntax not right regex. in js regex should wrapped /.../ / called regex delimiter.

also regex can refactored efficiency this:

/^(?=.*?[a-z])(?=.*?[a-z])(?=.*?[\d\w]).{8,}$/ 

updated jsfiddle