Filter Alert Javascript, how to -

i saw code time ago, , planning list hrefs of website, want filter it

 var arr = [], l = document.links;  for(var i=0; i<l.length; i++) {    arr.push(l[i].href);  }  alert(arr); 

i need code display links contains text in it

for example show in alert links contains in href ....?

day=20, ?day=22, , ?day=25

i tried add 1 if before .push, nothing worked, showed blank alert :(

last thing, if in place of alert want open in new tab each link, can give me direction or simplest way ;)

in modern browsers can this:

var links = document.queryselectorall('a[href*="day"]'); 

that give nodelist of link elements contain day in href. can filter hrefs in array:

var hrefs = array.prototype.map.call(links, function(link){   return link.href; });