sx/docs/fork-c/S0.3-reuse-delete-ledger.md

S0.3 — A–E6 reuse / delete ledger

Authority: runs/stdlib/design/fork-c-deepdive/reconciled.md (§6 roadmap + per-phase deletion lists, §8 fold-in) + runs/stdlib/design/migration.md ("what happens to already-merged A–E6 work") + planspec-r3.json (S0.3). Base: wt-stdlib-base @ 1f75528. Symbol/file refs are grounded against the base tree. This is documentation only — no code change.

This ledger is the contract the later phases execute against: every load-bearing A–E6 artifact is mapped to REUSED (with its Fork C home) or DELETED/TRANSITIONAL (with the S3/S6 phase that removes it). A–E6a stays merged; the transitional E6b src is never merged (see S0.2-…).

A. REUSED — A–E6 work that becomes Fork C infrastructure

A–E6 artifact (base location)	Fork C home	phase
Phase A import facts — RawDeclRef / RawAuthor / ModuleDecls / NamespaceEdges (src/imports.zig), built in resolveImports (core.zig)	seed DeclId construction — DeclTable keys every RawDeclRef into a stable DeclId (source + name + AST ptr + DeclKind); namespace members get ids	S1
Phase B visibility — collectVisibleAuthors / collectNamespaceAuthors (src/ir/resolver.zig), "the one graph iterator" over flat_import_graph/namespace_edges	resolver internals — become the resolver's visibility walk, with own-wins / single-flat-visible / ≥2-ambiguous verdicts above them, producing ResolvedRef	S2
Phase C callable selection	ResolvedRef.function / .type_function keyed by DeclId	S2 (select) → S3 (consume)
Phase D nominal identity — internNominal / updatePreservingKey + the nominal_id == 0 ≡ structural intern ordinal-0 byte-identity rule (src/ir/types.zig, lower.zig)	reused inside materialization — materializeType(ResolvedTypeNode) interns in old scan order with ordinal 0 for non-colliding decls ⇒ byte-identical single-author output	S3 (+ green-lock every phase)
E-series selection rules — own-wins / not-visible / ambiguity / direct-flat (the E1–E6a behaviors)	resolver behavior + regression tests (the baseline-green corpus is the mirror oracle)	S2 behavior; regressions locked S0
CP rule — body-author == layout-author	keyed by InstantiationId{template_decl, resolved_args} in the fact store	S4
E6BR routed-signature cases (the E6BR-1…4 behavioral cells)	resolver-signature regressions — the resolver walks every signature reference position; cases live in the resolver-target corpus, flip at S3.9	S3.9
FFI foreign_class_map consumers + 116-class corpus	parallel DeclIds land at S1 (map still the consumer); foreign classes keyed by DeclId at S4; runtime names stay payload strings on facts	S1 → S4

B. DELETED / TRANSITIONAL — removed in S3/S6

artifact (base location)	why it goes	removal phase
Stateless type_bridge leaves — resolveAstType / resolveTypeName / resolveInline{Enum,Union,Struct,ErrorSet} / resolveParameterizedType / resolveErrorType (src/ir/type_bridge.zig); the whole type_bridge.zig (E6b renamed the entry leaf resolveAstTypeNoAuthorSelection)	no-author findByName leaves — replaced by materializeType(ResolvedTypeNode) which cannot take a name	selectors S3; file S6
TypeResolver.resolveName / resolveNamed (src/ir/type_resolver.zig) (E6b: resolveNamedGlobalNoAuthorSelection)	name→global resolution; superseded by the resolver	S3 (name-selection) / S6 (resolveName*)
Old name selectors — selectNominalLeaf, resolveNominalLeaf, moduleTypeAuthor, namedRefTid, flatTypeAuthorCount, nameAuthoredAsTypeAnywhere, selectModuleConst (+ const-source pins), selectGenericStructHead, headTypeGate, headFnLeak, flatFnAuthor*, the name-selection in resolveTypeCallWithBindings/resolveParameterizedWithBindings (src/ir/lower.zig)	the duality leak — replaced by ResolvedRef/ResolvedTypeNode consumed in lowering	S3
*_by_source mirrors + source pins (src/ir/program_index.zig) + their writers + the lower.zig unified writers	dual-write mirrors of the global maps — superseded by the DeclId-keyed fact store	S4
type_decl_tids (src/ir/types.zig, lower.zig)	name→TypeId mirror — superseded by DeclId facts	S4/S6
ShadowTypeDecl / shadow-slot reservation helpers (src/ir/lower.zig) + lower-side nominal selectors	shadow reservation is a name-keyed pre-pass artifact — subsumed by DeclId pre-pass	S3/S4
TypeTable.findByName / findUniqueByName (src/ir/types.zig)	the global name table — deleted last (after the ~15 category-(b) stdlib lookups are re-homed to resolved-once DeclIds, per the §6 critical ordering constraint)	S6
the type-reference choke-point + route-all engine (resolveRegistrationSigTypeInSource / sig_registration_mode)	transitional E6b src — never merged; destined for deletion under Fork C	S3/S6 (already off-baseline)
the grep gate e6br_gate.test.zig (+ its ir.zig import)	transitional E6b src — never merged; unnecessary once the leaf it polices is gone	S6 (already off-baseline)
the S2→S3 assert-only Debug mirror	a test oracle, not a code path — must be deleted in the same S3.10 commit that removes the last old selector	S3.10

C. Dropped / absorbed / superseded plan items

• E6c / E6d / E6e (protocol / foreign / type-fn per-kind identity): DROPPED as steps. They become resolver behavior + regression tests — a whole-AST resolver walks every reference position (annotation, size_of, dispatch head, Self, vtable), closing the protocol surface the per-kind patch structurally could not (reconciled §4 T4).
• F (namespace resolver + 0104): ABSORBED into S2 as resolver internals (namespace_edges → ResolvedRef.namespace / member).
• H (constructor heads): ABSORBED into S3 materializeType over resolved generic/protocol/type-fn heads.
• I (protocol + foreign selection, loud-on-≥2): ABSORBED into S2 selection + S4 DeclId facts.
• K (delete dead readers): SUPERSEDED by the S4 DeclId-keyed fact store + the S6 deletions — "just delete the maps" is upgraded to "replace with DeclId facts."
• the per-kind taxonomy: REIFIED as the ResolvedRef union itself; the exhaustive switch is the live taxonomy check (the grep gate is gone because the leaf it policed no longer exists).

D. Acceptance (S0.3) — self-check

• ✅ Every load-bearing A–E6 artifact mapped to REUSED (with Fork C home) or DELETED/TRANSITIONAL (with the S3/S6 phase that removes it) — tables A & B; covers Phase A import facts → DeclId seed; B collectVisibleAuthors → resolver internals; C callable selection → ResolvedRef.function/type_function; D internNominal + ordinal-0 byte-identity → materialization; E-series rules → resolver behavior + regressions; CP → InstantiationId; the stateless type_bridge/type_resolver leaves, *_by_source mirrors + source pins, type_decl_tids/shadow helpers + lower-side selectors, the choke-point + route-all + grep gate → S3/S6 deletion.
• ✅ States E6c/d/e dropped and F/H/I/K absorbed/superseded — table C.
• ✅ No code change.