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doc/md022.md

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+# MD022 - Headings should be surrounded by blank lines
+
+Tags: blank_lines, headers, headings
+
+Aliases: blanks-around-headers, blanks-around-headings
+
+Parameters:
+
+* `lines_above`: Blank lines above heading (`integer`, default `1`)
+* `lines_below`: Blank lines below heading (`integer`, default `1`)
+
+Fixable: Most violations can be fixed by tooling
+
+This rule is triggered when headings (any style) are either not preceded or not
+followed by at least one blank line:
+
+```markdown
+# Heading 1
+Some text
+
+Some more text
+## Heading 2
+```
+
+To fix this, ensure that all headings have a blank line both before and after
+(except where the heading is at the beginning or end of the document):
+
+```markdown
+# Heading 1
+
+Some text
+
+Some more text
+
+## Heading 2
+```
+
+The `lines_above` and `lines_below` parameters can be used to specify a different
+number of blank lines (including 0) above or below each heading.
+
+Note: If `lines_above` or `lines_below` are configured to require more than one
+blank line, [MD012/no-multiple-blanks](md012.md) should also be customized.
+
+Rationale: Aside from aesthetic reasons, some parsers, including `kramdown`, will
+not parse headings that don't have a blank line before, and will parse them as
+regular text.