pandoc/test/command/5845.md

% pandoc -t native
\parbox{1em}{#1}
^D
[ Para [ Str "\\parbox{1em}{#1}" ] ]

% pandoc -t native
\newcommand{\highlight}[1]{\colorbox{yellow}{\parbox{\dimexpr\linewidth-2\fboxsep}{#1}}

Hello World
^D
[ Para
    [ Str "\\newcommand{"
    , RawInline (Format "tex") "\\highlight"
    , Str "}[1]{\\colorbox{yellow}{\\parbox{"
    , RawInline (Format "tex") "\\dimexpr"
    , RawInline (Format "tex") "\\linewidth-2"
    , RawInline (Format "tex") "\\fboxsep"
    , Str "}{#1}}"
    ]
, Para [ Str "Hello World" ]
]