# REVIEW — Phase `lex` (Adversary)

## Verdicts

### D1: PASS @2026-06-15T04:02Z
Cold-run evidence:
- `tokenize("42")` → `[('NUMBER', 42), ('EOF', None)]`, value is `<class 'int'>` ✓
- `tokenize("3.14")` → `NUMBER(3.14)` as float ✓
- `tokenize(".5")` → `NUMBER(0.5)` as float ✓
- `tokenize("10.")` → `NUMBER(10.0)` as float ✓
Regex `\d+\.?\d*|\.\d+` correctly handles all three float forms.

### D2: PASS @2026-06-15T04:02Z
Cold-run evidence:
- `tokenize("1+2*3")` → `['NUMBER', 'PLUS', 'NUMBER', 'STAR', 'NUMBER', 'EOF']` ✓
- All six operators (`+ - * / ( )`) mapped to correct kinds ✓
- Plan cold-verify: `tokenize('3.5*(1-2)')` → `[('NUMBER', 3.5), ('STAR', '*'), ('LPAREN', '('), ('NUMBER', 1), ('MINUS', '-'), ('NUMBER', 2), ('RPAREN', ')'), ('EOF', None)]` ✓

### D3: PASS @2026-06-15T04:02Z
Cold-run evidence:
- `tokenize("  12  +  3 ")` → `['NUMBER', 'PLUS', 'NUMBER', 'EOF']` ✓
- `tokenize("1 @ 2")` raises `LexError: unexpected character '@' at position 2` ✓
- Error message contains offending char and position ✓
- Letters and `$` also raise LexError with position ✓
- Tabs skipped correctly ✓

### D4: PASS @2026-06-15T04:02Z
Cold-run evidence:
```
Ran 21 tests in 0.000s

OK
```
All 21 tests pass, 0 failures. Test suite covers D1–D3 including `"  12  +  3 "`, `"3.5*(1-2)"`, and `"1 @ 2"` raising `LexError`.

## Adversarial probes (no failures found)
- Empty string `""` → `[EOF]` (correct)
- Whitespace-only `"   "` → `[EOF]` (correct)
- `.5+10.` → two floats with operator between (correct)
- Newline raises LexError — consistent with plan (plan specifies only spaces/tabs are skipped)
- Position reporting is 0-indexed and accurate

## Conclusion
All four DoD gates PASS. No defects found. Builder may mark STATUS as DONE.