user-tag.html

<!doctype html>
<meta charset="utf-8">
<meta name="viewport" content="width=device-width, initial-scale=1">
<title>custom tags</title>
<h3>custom tags</h3>

<a user="0"></a> <br>
<a user="1"></a> <br>
<a user="2"></a> <br>

<script>
var users=document.querySelectorAll('a[user]')

var user_data={
0:['Dario Cangialosi','dario.cangialosi'],
1:['Firstname Lastname','profile.address'],
2:['Mario Rossi','mario.rossi.work'],
}

for(var iuser of users){
var uid=iuser.getAttribute('user')
iuser.text=user_data[uid][0]
iuser.href='/u/'+user_data[uid][1]
}
</script>