Macro comet::replace_self

macro_rules! replace_self {
    (
        $self:ident,
        {
            {
                {
                    self
                    $($rest:tt)*
                }
                [$($expanded:tt)*]
            }
        }
    ) => { ... };
    (
        $self:ident,
        {
            {
                {
                    $chunk:tt
                    $($rest:tt)*
                }
                [$($expanded:tt)*]
            }
        }
    ) => { ... };
    (
        $self:ident,
        {
            {
                {}
                [$($expanded:tt)*]
            }
        }
    ) => { ... };
    (
        $self:ident,
        $($e:tt)*
    ) => { ... };
}