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+# Generics — closing summary (2026-10-16)
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+
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+Branch **`resolve-check`**, tree clean. Suite **214/214**; fixpoint
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+**OK (3,710,201 bytes)**; corpus **372 OK / 0 crash**.
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+
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+## Supported today
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+
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+ISO 10514-2 **refinement generics**, instantiated by re-parsing the
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+generic source with a substitution scope, driven by the session driver.
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+
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+| Feature | Syntax | Notes |
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+| --- | --- | --- |
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+| Type parameters | `MODULE Box (T : TYPE)` | `Box(INTEGER)` |
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+| Value parameters | `MODULE Buf (size : CARDINAL)` | `Buf(10)`; template binds a placeholder |
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+| Procedure parameters | `MODULE Sort (E : TYPE; Compare : PROCEDURE(a,b : E) : INTEGER)` | actual is `Mod.Proc` |
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+| Constraints | `MODULE OrdBox (T : TYPE (ORDINAL))` | `ORDINAL`, `INTEGER`, `REAL`, `POINTER`, `SCALAR` |
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+| Multiple parameters | `MODULE Pair (T : TYPE; U : TYPE)` | both bound |
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+| Nested generics | `MODULE WrapB = Wrap(IntBox.Box)` | an instance's exported type as an actual |
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+| Def + impl | `DEFINITION`/`IMPLEMENTATION MODULE X = G(...)` | both required; template not emitted |
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+
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+Constraints and actual-kind are checked at instantiation (`233` on
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+mismatch). Suite: `GenericProg`, `PairProg`, `BufProg`, `g_badbuf`,
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+`SortProg`, `OrdProg`, `g_realbox`, `GWrapProg`.
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+
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+## Mechanism (recap)
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+
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+- Driver records each generic's def/impl file; on a refinement re-opens
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+ it, sets the instantiation context, re-parses and lowers the unit.
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+- Formals bind via `SymTab.EnterTypeParamBound` (types),
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+ `SetSymVal` on a `CONST` (values), or `SymTab.AliasProc` +
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+ `Lower.AliasProc` (procedures; `ProcBaseByUid` fixes mangling after
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+ the instance scope is popped).
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+- Qualified actuals (`Mod.Name`) are classified as proc or type, which
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+ is how both procedure parameters and nested generics reach a name
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+ without an import.
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+
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+## Deliberately not done
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+
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+- **Instance dedup** — not needed: each refinement declares its own
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+ module (`BoxA = OrdBox(INTEGER)`, `BoxB = OrdBox(INTEGER)` coexist
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+ cleanly; verified). The only "same instance twice" case is a
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+ refinement's DEFINITION and IMPLEMENTATION, which must instantiate
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+ the generic's def and impl respectively.
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+- **`GENERIC CLASS`** — needs a **design decision**, not extension: the
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+ current machinery instantiates *modules* by re-parsing a source file.
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+ A generic *class* has no natural refinement form yet (a class is a
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+ type declared inside a module; instantiating it would re-parse its
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+ enclosing module, or require a `TYPE C = GClass(args)` type-refinement
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+ affordance). Until that syntax is chosen, this stays open.
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+
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+## Résumé
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+
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+```sh
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+cd .../m2compiler-V3/compiler
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+./M2 tests/g_ordbox.def tests/g_ordbox.mod tests/g_intbox.def \
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+ tests/g_intbox.mod tests/g_wrap.def tests/g_wrap.mod \
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+ tests/g_wrapb.def tests/g_wrapb.mod tests/g_wrapprog.mod # GWrapProg -> 42
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+```
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