fn do_env_dir<'a, 'b, 'c, Pos: StringPosition, T: FromLaTeXToken<'a, Pos>, State: ParserState<'a, Pos, T>>(
arg: &&'a str,
e: &'b mut Environment<'a, Pos, T>,
parser: &'c mut LaTeXParser<'a, Pos, T, State>,
)fn do_env_dir<'a, 'b, 'c, Pos: StringPosition, T: FromLaTeXToken<'a, Pos>, State: ParserState<'a, Pos, T>>(
arg: &&'a str,
e: &'b mut Environment<'a, Pos, T>,
parser: &'c mut LaTeXParser<'a, Pos, T, State>,
)