macros_nested_env.test

<<< tex
\newenvironment{brak}[1]{\langle #1:}{:#1\rangle}
\begin{brak}{a} x \begin{brak}{b} y \end{brak} z \end{brak}
>>> native
[ ESymbol Open "\10216"
, EIdentifier "a"
, ESymbol Rel ":"
, EIdentifier "x"
, ESymbol Open "\10216"
, EIdentifier "b"
, ESymbol Rel ":"
, EIdentifier "y"
, ESymbol Rel ":"
, EIdentifier "b"
, ESymbol Close "\10217"
, EIdentifier "z"
, ESymbol Rel ":"
, EIdentifier "a"
, ESymbol Close "\10217"
]