The opposite of hex().

string_hex

function string_hex(value, padding) {
    if (padding == undefined) padding = 0;
    
    var s = sign(value);
    var v = abs(value);
    
    var output = "";
    
    while (v > 0)  {
        var c  = v & 0xf;
        output = chr(c + ((c < 10) ? 48 : 55)) + output;
        v = v >> 4;
    }
    
    if (string_length(output) == 0) output = "0";
    
    return ((s < 0) ? "-" : "") + string_pad(output, "0", padding);
}