PHP数组到YAML

I would like to update some values from a YAML file. My original YAML file is:

---
theme_name: origin
meta_images: true
disqus_account: changeme
show_comments: false

globals:
  - 
    name: phone
    display: Phone
    value: foo
  -
    name: email
    display: Email
    value: foo2

After reading the YAML file in using parseFile() I get the following array in PHP:

Array

(
[theme_name] => origin
[meta_images] => 1
[disqus_account] => changeme
[show_comments] => 
[globals] => Array
    (
        [0] => Array
            (
                [name] => phone
                [display] => Phone
                [value] => foo
            )

        [1] => Array
            (
                [name] => email
                [display] => Email
                [value] => foo2
            )

        [phone] => foo
        [email] => foo3
    )

)

After updating the values I parsing it back to YAML using Symfony's YAML dump():

---
theme_name: origin
meta_images: true
disqus_account: changeme
show_comments: false
globals:
  0:
    name: phone
    display: Phone
    value: foo
  1:
    name: email
    display: Email
    value: foo2
  phone: foo
  email: foo3

I would like this to be parsed into the following YAML:

Desired YAML

---
theme_name: origin
meta_images: true
disqus_account: changeme
show_comments: false

globals:
  - 
    name: phone
    display: Phone
    value: foo
  -
    name: email
    display: Email
    value: foo2

Is this possible using Symfony, or PHP's built-in YAML methods?