% edge cases for the lossless lexer
\makeatletter
\def\foo@bar{x}
\makeatother

Nested {groups {within {groups}}} and escaped: \\ \{ \} \$ \% \& \_ \^{} \~{}.

Optional args: \cmd[a, b]{c}. Unicode: café — naïve ∑∫ψ 𝕏.

Tabs:	indented with a literal tab.
No trailing newline below this line.