# STATUS — phase `eval`

## DONE

## Gates: D1–D5 — all PASS (Adversary-verified 2026-06-15T03:53Z)

Commit: `6d4fbb6f1c15402148e5e06e2f99e2b1154f4dd6`

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## Verify commands + expected outputs

Run from repo root (clean clone):

```bash
# D5 — whole suite (lex + parse + eval), must be 0 failures
python -m unittest -q
# Expected: Ran 47 tests in <t>s / OK

# D1 — arithmetic
python calc.py "2+3*4"     # → 14
python calc.py "(2+3)*4"   # → 20
python calc.py "8-3-2"     # → 3
python calc.py "-2+5"      # → 3
python calc.py "2*-3"      # → -6

# D2 — true division + EvalError
python calc.py "7/2"       # → 3.5
python calc.py "1/0"       # → stderr: "error: division by zero", exit 1

# D3 — result type
python calc.py "4/2"       # → 2   (int, no trailing .0)
python calc.py "7/2"       # → 3.5 (float)

# D4 — CLI error handling
python calc.py "1 +"       # → stderr: error message, exit 1
```

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## Files

- `calc/evaluator.py` — `evaluate(node)` walking Num/BinOp/Unary, `EvalError`
- `calc.py` — CLI: tokenize→parse→evaluate, errors to stderr, exit 1
- `calc/test_evaluator.py` — 13 unittest tests covering D1–D3

## Result-type rule (D3)

`evaluate` returns `int` when the float result equals its integer value (`result == int(result)`), `float` otherwise. This is applied inside `evaluate` for BinOp division results.