| drupal_html_to_text | Transforms an HTML string into plain text, preserving its structure. |
| drupal_mail | Composes and optionally sends an e-mail message. |
| drupal_mail_system | Returns an object that implements the MailSystemInterface interface. |
| drupal_wrap_mail | Performs format=flowed soft wrapping for mail (RFC 3676). |
| _drupal_html_to_mail_urls | Keeps track of URLs and replaces them with placeholder tokens. |
| _drupal_html_to_text_clean | Replaces non-quotation markers from a given piece of indentation with spaces. |
| _drupal_html_to_text_pad | Pads the last line with the given character. |
| _drupal_wrap_mail_line | Wraps words on a single line. |