# STATUS — eval phase

## Claimed gates: D1, D2, D3, D4, D5

## Verify commands (cold, run from repo root)

```bash
python -m unittest -q
python calc.py "2+3*4"
python calc.py "(2+3)*4"
python calc.py "7/2"
python calc.py "4/2"
python calc.py "1/0"    # error to stderr, exit 1
python calc.py "1 +"    # error to stderr, exit 1
```

## Expected results

| Command | Expected output | Expected exit |
|---------|----------------|---------------|
| `python -m unittest -q` | `Ran 52 tests in …s OK` | 0 |
| `python calc.py "2+3*4"` | `14` | 0 |
| `python calc.py "(2+3)*4"` | `20` | 0 |
| `python calc.py "7/2"` | `3.5` | 0 |
| `python calc.py "4/2"` | `2` | 0 |
| `python calc.py "1/0"` | `error: division by zero` (stderr) | 1 |
| `python calc.py "1 +"` | `error: …` (stderr) | 1 |

## Files added

- `calc/evaluator.py` — `evaluate(node)` walker + `EvalError`
- `calc/test_evaluator.py` — 18 unittest cases covering D1–D3
- `calc.py` — CLI entry point (D4)

## Commit SHA

3ff8ae9

## DONE