fn check_nested_assertion(&mut self) -> Option<Group> {
        if let Some(TokenTree::Group(group)) = self.tokens.front() {
            if group.delimiter() == Delimiter::Parenthesis {
                if let Some(TokenTree::Group(group)) = self.pop() {
                    return Some(group);
                } else {
                    unreachable!();
                }
            }
        }
        None
    }
/// Check if we have a nested assertion here.
Check if we have a nested assertion here.
Check if we have a nested assertion here .
fn check_nested_assertion(&mut self) -> Option<Group> {
        if let Some(TokenTree::Group(group)) = self.tokens.front() {
            if group.delimiter() == Delimiter::Parenthesis {
                if let Some(TokenTree::Group(group)) = self.pop() {
                    return Some(group);
                } else {
                    unreachable!();
                }
            }
        }
        None
    }
fn check_nested_assertion ( & mut self ) -> Option < Group > { if let Some ( TokenTree :: Group ( group ) ) = self . tokens . front ( ) { if group . delimiter ( ) == Delimiter :: Parenthesis { if let Some ( TokenTree :: Group ( group ) ) = self . pop ( ) { return Some ( group ) ; } else { unreachable ! ( ) ; } } } None }
Check if we have a nested assertion here.
Check if we have a nested assertion here .
&mut self