# BACKLOG — Phase `parse`

## Build backlog

- [x] D1 — Precedence: implement grammar with `*`/`/` tighter than `+`/`-`
- [x] D2 — Left associativity: iterative left-fold in `_expr` and `_term`
- [x] D3 — Parentheses: `_primary` handles `LPAREN expr RPAREN`
- [x] D4 — Unary minus: `_unary` handles leading `-` recursively
- [x] D5 — Errors: `ParseError` raised for all malformed inputs
- [x] D6 — Tests green: `calc/test_parser.py` with 23 structural assertions

## Adversary findings
(none yet)