Method parse_prefix

crates/hll-to-ir/src/parser.rs:940–969

(&mut self)

                && trial.match_assign()
            {
                *self = trial;
                let rvalue = self.parse_assignment()?;
                return Ok(Expression::Assignment {
                    target: Box::new(target),
                    rvalue: Box::new(rvalue),
                });
            }

            self.pos = saved_pos;
        }

        let left = self.parse_or()?;
        if self.match_assign() {
            let target = self.expression_to_target(left)?;
            let rvalue = self.parse_assignment()?;
            Ok(Expression::Assignment {
                target: Box::new(target),
                rvalue: Box::new(rvalue),
            })
        } else if let Some(op) = self.match_compound_assign() {
            // `lhs OP= rhs` desugars to `lhs = lhs OP (rhs)`, so lhs evaluates twice.
            // HLL assignment targets are simple lvalues, so that is benign.
            let target = self.expression_to_target(left.clone())?;
            let rhs = self.parse_assignment()?;
            let rvalue = Expression::Binary {
                op,
                left: Box::new(left),
                right: Box::new(rhs),
            };
            Ok(Expression::Assignment {
                target: Box::new(target),
                rvalue: Box::new(rvalue),
            })