fn try_pop_lhs<'s, 'b>(
entered: &Stack<'b, EnteredDelimiter<'s, 'b>>,
alloc: &'b Bump
) -> Option<(&'s Syntax<'s>, Stack<'b, EnteredDelimiter<'s, 'b>>)>
fn try_pop_lhs<'s, 'b>(
entered: &Stack<'b, EnteredDelimiter<'s, 'b>>,
alloc: &'b Bump
) -> Option<(&'s Syntax<'s>, Stack<'b, EnteredDelimiter<'s, 'b>>)>