Question

I have 3 functions (they are minimalized so they might be difficult to read) listed below – i0, t0, and is.

is() and t0() both pull data from the DOM with this line

  var c=document.forms[a].elements;

would it be better to pull the data from the DOM in i0(), and then pass it to is() and t0()?

That way I would only pull data from the DOM once, but then I would need an extra variable to store it in an pass it to the two functions.

i0():

function i0()
  {
  if(t0())
    {
    var a=is('f0');
    s0('bi0.php',a,s2);
    }
  }

t0:

function t0()
  {
  var a=document.forms['f0'].elements;
  a1="Please enter your credentials";
  a2="That email is not registered";
  a3="Incorrect credentials - Reset your password?";
  if(c0(a,a1,'fb1')&&c2(a[1],a2,'fb1')&&c3(a[2],a3,'fb1'))
    {
    return 1;
    }
  else
    {
    return 0;
    }
  }

is():

function is(a)
  {
  var b='';
  var c=document.forms[a].elements;
  for(i=0;i<c.length;i++)
    {
    if(c[i].name)
      {
      if(c[i].type=='checkbox'&&c[i].checked==false)
        {
        b+=c[i].name+"=NULL&";
        }
      else
        {
        b+=c[i].name+"="+c[i].value+"&";
        }
      }
    }
    b=b.slice(0,-1);
  return b;
  }

Answer 1

function i0(a){
    t0() && (a=is('f0'), s0('bi0.php', a, s2)); // just so I can use the comma like this
}

// or

function i0(){
    t0() && s0('bio.php', is('f0'), s2);
}

function t0(){
    var a = document.forms['f0'].elements,
       a1 = "Please enter your credentials",
       a2 = "That email is not registered",
       a3 = "Incorrect credentials - Reset your password?";

    return +( c0(a,a1,'fb1') && c2(a[1],a2,'fb1') && c3(a[2],a3,'fb1') );
}

function is(a){
    var b = '',
        c = document.forms[a].elements;

    for( var i=0, l=c.length; i<l; i++ ){
        c[i].name
            ? c[i].type == 'checkbox' && !c[i].checked && b += c[i].name + '=NULL&'
            : b += c[i].name + '=' + c[i].value + '&';
    }
    return ( b = b.slice(0, -1) );
}

---

to answer your actual question, yes doing a single select on document.forms['f0'].elements will make things slightly faster in some browsers, but it’s a micro-optimization that I suspect will only be faster in old browsers (IE6) due to the hash-lookup.