# Two-phase refactor — slice 9 (brace / set literals)

Branch `ast-stage-c`.  Suite **178/178**; self-hosting fixpoint **OK**
(**3,024,098 bytes**; slice 8 was 3,021,285).

## What landed

| Literal | AST |
| --- | --- |
| `{e, a..b}` | `NkSetLit(elements…)`, ranges as `NkSubrange` |
| `T{e, …}` | `NkBraceLit(elements…)` |

`SetLit`/`TypedBraceLit` create the node before their elements and pass
it to `SetElem`/`BraceElem`, which append each element's node (a range
becomes `NkSubrange`; a `BY` repeat keeps the value node).  `Fact` now
keeps the brace node (`astBrace`) instead of discarding it, marking
`astIsLit` so it survives the `Fact` reset; set literals likewise.

## Verified (temporary `AST.Dump` of `astUnit`, then removed)

```modula2
b := {1, 3..5};
b := BITSET{0, 2}
```

gave `NkSetLit(1, NkSubrange(3,5))` and `NkBraceLit(0, 2)`.

## Deliberately deferred

- `ResultComp` call-result suffixes (`F()[i]`, `F().f`, `F()^`).
- Imports, `CLASS`, nested modules in the unit AST.
- `Lower` + `.ssa` byte-compare.

## Next

`ResultComp`, then imports/`CLASS`/nested modules, then `Lower`.