pub fn pop_tail(&mut self) -> Option<u8> {
        if self.is_empty() {
            None
        } else {
            self.tail = self.tail.checked_sub(1).unwrap_or(N - 1);
            Some(self.buf[self.tail])
        }
    }
/// Pop content type from tail.
Pop content type from tail.
Pop content type from tail .
pub fn pop_tail(&mut self) -> Option<u8> {
        if self.is_empty() {
            None
        } else {
            self.tail = self.tail.checked_sub(1).unwrap_or(N - 1);
            Some(self.buf[self.tail])
        }
    }
pub fn pop_tail ( & mut self ) -> Option < u8 > { if self . is_empty ( ) { None } else { self . tail = self . tail . checked_sub ( 1 ) . unwrap_or ( N - 1 ) ; Some ( self . buf [ self . tail ] ) } }
Pop content type from tail.
Pop content type from tail .
&mut self
&mut self