We've added a number of functions recently to help making building easier:
MIME_HEADER_DECODE- Decodes email header fields encoded in accordance with RFC 2047.IS_EMAIL- Checks if a string follows email standard. It does not verify that the email exists.IS_URL- Checks if a string follows the URL standard.IS_IPV4- Checks if a string is an IPv4 address.IS_IPV6- Checks if a string is an IPv6 address.IS_XML- Checks if a string is valid XML.IS_JSON- Checks if a string is valid JSON.IS_YAML- Checks if a string is valid YAML.
