Parsing/Shunting-yard algorithm: Difference between revisions

self.get(self.lenlast() - 1).mapcloned(|value| value.clone())

let ret = match input {

'0'...'9' => Ok(Token::Digit(input.to_digit(10).unwrap() as Number)),

'+' => Ok(Operator::new_token('+', 1, true, |x, y| x + y)),

'-' => Ok(Operator::new_token('-', 1, true, |x, y| x - y)),

'*' => Ok(Operator::new_token('*', 2, true, |x, y| x * y)),

'/' => Ok(Operator::new_token('/', 2, true, |x, y| x / y)),

'^' => Ok(Operator::new_token('^', 3, false, |x, y| x.powf(y))),

'(' => Ok(Token::LeftParen),

')' => Ok(Token::RightParen),

_ => return Err(input),

};