pub fn number_value(&self) -> Option<SafasNumber> {
        match self {
            SafasCell::Number(number)   => Some(*number),
            SafasCell::Nil              => Some(SafasNumber::Plain(0)),
            _                           => None
        }
    }
///
/// If this is a number, the value of the number
///
If this is a number, the value of the number
If this is a number the value of the number
pub fn number_value(&self) -> Option<SafasNumber> {
        match self {
            SafasCell::Number(number)   => Some(*number),
            SafasCell::Nil              => Some(SafasNumber::Plain(0)),
            _                           => None
        }
    }
pub fn number_value ( & self ) -> Option < SafasNumber > { match self { SafasCell :: Number ( number ) => Some ( * number ) , SafasCell :: Nil => Some ( SafasNumber :: Plain ( 0 ) ) , _ => None } }
If this is a number, the value of the number
If this is a number the value of the number
&self
&self