Сергей Мельников

$("#form_name").on("submit", function(e) {
  e.preventDefault()
  // do what you need
  this.submit()
})

var arr = [
  { price: 10, amount: 10 },
  { price: 12, amount: 12 },
  { price: 9, amount: 7 },
  { price: 17, amount: 8 },
  { price: 4, amount: 2 }
]

arr
  .sort(function(a, b) {
    return a.price - b.price
  })
  .reverse()
  .map(function(item, i) {
    item.index = i + 1 
  })

console.log(arr)
/*
[
  { price: 17, amount: 8, index: 1 },
  { price: 12, amount: 12, index: 2 },
  { price: 10, amount: 10, index: 3 },
  { price: 9, amount: 7, index: 4 },
  { price: 4, amount: 2, index: 5 }
]
*/

var data = { 
  a: { 
    b: { 
      c: { 
        d: { 
          e: "Hello World!" 
        } 
      } 
    } 
  } 
}
function from(target, path) {
  return path.split(".").reduce(function(data, key) { 
    return data && data[key] 
  }, target)
}
console.log(from(data, "a.b.c.d.e")) // "Hello World!"
console.log(from(data, "a.a.a.a.a")) // undefined

const walk = data => {
  if (!data) return;
  for (let i = 0; i < data.length; i++) {
    for (let l = 0; l < data.length; l++) {
      if (data[l].left > data[i].left && data[l].right < data[i].right) {
        data[i].children = data[i].children || []
        data[i].children.push(data.splice(l, 1)[0])
        l--
      }
    }
    walk(data[i].children)
  }
  return data
}

const list = tree => {
  let ul = document.createElement("ul")
  for (let i = 0; i < tree.length; i++) {
    let li = document.createElement("li")
    li.textContent = tree[i].title
    ul.appendChild(li)
    if (tree[i].children) li.appendChild(list(tree[i].children))
  }
  return ul
}

let tree = walk(data)

console.log(tree)

let listNode = list(tree)

console.log(listNode)

var str = "слово1 слово2 [слово слово слово] слово3";
var result = [];
str.replace(/(\[.+?\]|\S+)/g, function(m) {
  result.push(m);
  return "";
})
console.log("Result:", result)
// ["слово1", "слово2", "[слово слово слово]", "слово3"]

<?php 
$message = "";
if (count($_POST)) {
  // обрабатываем данные формы
  // задаем значение переменной $message
}
?>

<?php if ($message) { ?>
<div id="error_message" style="width:200px; color:red; position:fixed; left:50%; margin-left:-100px; text-align:center;"></div>
<?php } else { ?>
  <form action="" method="post" target="error_message">
    <input name="reg_nickname" type="text" placeholder="Введите имя" required />
    <input id="id_reg_email" name="reg_email" type="email" placeholder="Введите e-mail" required />
    <input id="id_reg_pass" name="reg_pass" type="password" placeholder="Введите пароль" required />
    <input id="id_reg_confirmpass" name="reg_confirmpass" type="password" placeholder="Подтвердите пароль" required />  
    <input type="submit" value="Зарегистрироваться" onclick="return check_email_pass();" style="margin-top:20px;" />
  </form>
<?php } ?>