# HTML declarations
Doctype on its own line should be one HtmlBlock:
<!DOCTYPE html>
Uppercase keyword:
<!DOCTYPE HTML PUBLIC "-//W3C//DTD HTML 4.01//EN" "http://www.w3.org/TR/html4/strict.dtd">
Element declaration:
<!ELEMENT br EMPTY>
Attribute list declaration:
<!ATTLIST greeting id ID #IMPLIED>
Indented (3 spaces, still valid):
<!DOCTYPE html>
Indented (4+ spaces, becomes indented code instead):
<!DOCTYPE not_a_block>
Mid-paragraph declaration should become inline raw HTML, not a block:
The doctype <!DOCTYPE html> is required for HTML5.