Method parse_callable_args

core/src/parser.rs:1339–1382

Parses the optional parameter list that may appear after a `FUNCTION` or `SUB` definition, including the opening and closing parenthesis.

(&mut self)

    /// Parses the optional parameter list that may appear after a `FUNCTION` or `SUB` definition,
    /// including the opening and closing parenthesis.
    fn parse_callable_args(&mut self) -> Result<Vec<VarRef>> {
        let mut params = vec![];
        let peeked = self.lexer.peek()?;
        if peeked.token == Token::LeftParen {
            self.lexer.consume_peeked();

            loop {
                let token_span = self.lexer.read()?;
                match token_span.token {
                    Token::Symbol(param) => {
                        let peeked = self.lexer.peek()?;
                        if peeked.token == Token::As {
                            self.lexer.consume_peeked();

                            let name = vref_to_unannotated_string(param, token_span.pos)?;
                            let (vtype, _pos) = self.parse_as_type()?;
                            params.push(VarRef::new(name, Some(vtype)));
                        } else {
                            params.push(param);
                        }
                    }
                    _ => {
                        return Err(Error::Bad(
                            token_span.pos,
                            "Expected a parameter name".to_owned(),
                        ));
                    }
                }

                let token_span = self.lexer.read()?;
                match token_span.token {
                    Token::Comma => (),
                    Token::RightParen => break,
                    _ => {
                        return Err(Error::Bad(
                            token_span.pos,
                            "Expected comma, AS, or end of parameters list".to_owned(),
                        ));
                    }
                }
            }
        }
        Ok(params)
    }

    /// Parses the body of a callable and returns the collection of statements and the position
    /// of the end of the body.