pandoc/test/command/shift-heading-level-by.md

% pandoc --shift-heading-level-by 1 -t native -s
---
title: My title
...

# First heading

## Second
^D
Pandoc
  Meta
    { unMeta =
        fromList [ ( "title" , MetaInlines [ Str "My title" ]) ]
    }
  [ Header 2 ( "first-heading" , [] , [] ) [ Str "First heading" ]
  , Header 3 ( "second" , [] , [] ) [ Str "Second" ]
  ]

% pandoc --shift-heading-level-by -1 -t native -s
---
title: Old title
...

# First heading

## Second

# Another top-level heading
^D
Pandoc
  Meta
    { unMeta =
        fromList
          [ ( "title" , MetaInlines [ Str "First heading" ] ) ]
    }
  [ Header 1 ( "second" , [] , [] ) [ Str "Second" ]
  , Para [ Str "Another top-level heading" ]
  ]