Commit Graph

16 Commits

Author SHA1 Message Date
agra
116af2359e lang: multi-iterable for loops — drop ':', add '..=', open ranges, arrow bodies
The for header is now a comma-separated list of iterables with a
positional capture group and no ':' separator:

    for xs (x) { }                    // collection
    for 0..n (i) { }                  // range (end exclusive)
    for 1..=5 (a) { }                 // ..= inclusive end
    for xs, 0.. (x, i) { }            // index idiom (replaces (x, i))
    for xs, ys (x, y) { }             // parallel (zip) iteration
    for xs (x) => sum += x;           // arrow body (full statement)

First-iterable-wins: the first iterable's length drives the loop and
must be bounded; the other positions follow by their own cursors (a
non-first range's end is not consulted or evaluated; a shorter
non-first collection is read past its length on mismatch). The old
single-iterable index capture is replaced by the trailing open range.

Capture/call disambiguation is positional: the paren group immediately
before '{' or '=>' is the capture, every earlier top-level group is a
call. 'for zip(a, b) (x, y)' calls zip; 'for f(n) { }' reads (n) as
the capture and errors with a parenthesize/add-capture hint. The old
':' form errors with a migration hint.

Lowering is unified across forms: one cursor slot per position (ranges
start at their start, collections at 0), all advanced together, the
first position's bound terminating. inline for keeps the single
bounded comptime range.

Migrated the full corpus (examples, library modules, issue repros,
in-source test strings). New coverage: examples/0050 (the full feature
surface) and examples/1149-1155 (seven diagnostic faces). specs.md For
Loop section + grammar rewritten; readme teaser updated.
2026-06-10 20:30:55 +03:00
agra
2b8041a828 cleanup: drop resolved-issue citations from src comments
Sweep all src/**.zig comments that cite resolved issues (issue NNNN /
fix-NNNN / KB-N): the invariant or mechanism each comment states is
kept; the historical citation is dropped, per the no-conclusion-comments
rule. Pure-history parentheticals are removed outright. References to
the 16 still-open issues (0030, 0041-0056) are untouched, as are test
NAMES carrying regression provenance (matching the sanctioned
"Regression (issue NNNN)" example-header convention).

Also removes the issues/0019-import-non-transitive-c-scope/ fixture dir
— the issue is superseded and its behavior is covered by
examples/0706-modules-import-non-transitive.sx (the .md writeup stays).
issues/0030's repro .sx stays: that issue is an open feature request.

Gate: zig build OK; zig build test 426/426; run_examples 541/0; zero
expected/ snapshot churn.
2026-06-10 16:34:17 +03:00
agra
a0390a63ab fix(diag): generic VALUE param ($N: u32) used as a field/annotation type → diagnostic (no .unresolved LLVM panic) [stdlib E3 attempt-3]
The generic-struct field checker (attempt-2) accepted ALL struct type
params as valid type-name leaves, including VALUE params. The parser
marks any reference to a struct's own param `is_generic` (so `x: T`
resolves without `$`), and it marks a value param `$N: u32` the same
way — so `Bad :: struct($N: u32) { x: N; }` instantiated `Bad(3)` slipped
past the unknown-type walk, resolved the field's type leaf to the
`.unresolved` sentinel, and panicked at LLVM emission instead of
diagnosing.

Distinguish TYPE params (`$T: Type`, `$T: SomeProtocol`, the `..$Ts`
pack) from VALUE params (`$N: u32`) using the binder's own classification
rule (lower.zig). A value param named in a type position now gets the
tailored "'N' is a value parameter, not a type" hint, exit 1, before
codegen. Two dispatch paths covered: the `is_generic` struct-field path
(reportIfValueParamInTypePosition) and the non-generic annotation path
(reportIfUnknownType in-scope filter). A value param in a VALUE position
(array dim `[N]u8`, `Vector` lane) still resolves.

Regression: 0172-types-value-param-as-field-type (panic-before / clean
diagnostic-after). 0171 and 0759 stay green; 499 markers, prior
byte-identical.
2026-06-08 09:02:54 +03:00
agra
a4906975bd fix(diag): undeclared type in a main-file generic struct field → diagnostic (no silent stub) [stdlib E3 attempt-2]
Closes the main-file carveout left by attempt-1 (4072689): a genuinely-
undeclared type used as a field type inside a MAIN-file GENERIC struct still
fell through the type leaf's empty-struct stub and silently compiled —
`Box :: struct($T: Type) { good: T; bad: MissingType; }` with `b : Box(s64)`
exited 0 and printed a value instead of reporting `unknown type 'MissingType'`.

Root cause: `UnknownTypeChecker` is the main-file diagnostic authority (the
type leaf defers to it for `.undeclared` names there), but
`checkStructFieldTypes` SKIPPED every generic struct outright ("its fields
reference `$T`, resolved at instantiation"), so the undeclared name was never
examined. The sibling `walkBodyTypes` `.struct_decl` arm skipped body-local
generic structs the same way.

Fix (semantic_diagnostics.zig, checker only — no leaf change):
- `checkStructFieldTypes`: stop skipping generic structs; walk the field
  types with the struct's OWN type params (`$T`, `$N`, `..$Ts`) passed as the
  in-scope set. A param name resolves; any OTHER bare name that is neither
  declared nor a generic param is reported. Value-param positions (a `Vector`
  lane count, a `$N: u32` arg) are still skipped inside
  `checkTypeNodeForUnknown` / `isValueParamPosition`.
- `walkBodyTypes` `.struct_decl`: same close for body-local structs — the
  local struct's own type params join the enclosing scope's in-scope params
  (so it can name both the outer fn's `$T` and its own), any other bare field
  type is still flagged.

The `..$Ts` pack field `(..$Ts)` parses to a `spread_expr` inside the tuple,
which hits `checkTypeNodeForUnknown`'s `else` arm — never walked — so the pack
examples (0538-0543, 0414) stay green. The checker walks only MAIN-file decls,
so library generic structs (List, Map) are untouched.

Regression: examples/0171-types-undeclared-type-in-generic-struct-field — the
reviewer's exact shape; `unknown type 'MissingType'` at the field, exit 1.
Fail-before on 4072689 (prints 7, exit 0), pass-after.

Gate: zig build; zig build test (423/423 + LSP corpus sweep 514); run_examples
498 passed / 0 failed (prior 497 byte-identical); m3te ios-sim build exit 0.
2026-06-08 08:36:45 +03:00
agra
023971cae5 feat(lang): universal backtick raw identifier — valid in value, decl, AND type position [F0.6]
AGRA ruling (attempt 4): `` `name `` is THE LITERAL identifier `name`, usable in
EVERY position — the backtick only means "treat this token as a plain identifier,
never the reserved keyword/type", and is never part of the name's text.

- Raw in TYPE position is now VALID (reverses attempt-2 "raw is not a type"):
  `parseTypeExpr` emits a raw `type_expr`; `TypeResolver.resolveNamed` gains a
  `skip_builtin` flag (threaded from `te.is_raw` via lower.zig + type_bridge) so a
  `` `s2 `` reference resolves to a `` `s2 ``-declared type (struct/enum/union/alias),
  else a normal "unknown type 's2'" error (reportIfUnknownType skips the builtin
  exemption when raw). Bare `s2` in type position stays the builtin int.
- Every declaration-name site is is_raw-exemptible: `is_raw` added to TypeExpr +
  StructDecl/EnumDecl/UnionDecl/ErrorSetDecl/ProtocolDecl/ForeignClassDecl/UfcsAlias/
  NamespaceDecl/ImportDecl/CImportDecl/LibraryDecl; parser threads name_is_raw to
  every decl parse fn; namespace imports carry it through imports.addNamespace.
  Typed-const path (`` `s2 : s64 : 5 ``) now threads name_span+is_raw (fixes the
  1:1-caret bug).
- Check<->exemption made structurally symmetric: checkBindingName/checkDeclName take
  is_raw as a REQUIRED argument and skip inside the check, so no call site can
  validate a name without honoring the exemption (the desync cause of prior rounds).
- Bare reserved-name declarations of every kind still error (0076 preserved);
  `#import c` foreign names stay auto-raw + bare-callable.

specs.md + readme.md updated to the universal model. issue 0089 RESOLVED banner
rewritten. Examples: replace 1139 (raw-not-a-type) with 0154 (raw type reference);
add 0155 (typed const + union tag) and 1141 (bare type-decl negatives).
Gate: zig build + zig build test + run_examples (426 passed, 0 failed).
2026-06-04 20:27:53 +03:00
agra
c0e1a5db82 feat(lang): reserved-name check covers :: const/fn/type decls + scope call rewrite to raw provenance [F0.6]
A bare reserved-type-name `::` declaration was silently accepted, and the
attempt-2 lowerCall rewrite then made a bare `s2 :: (…) {…}` function callable —
bypassing the backtick rule for handwritten sx. The reserved-name binding check
covered `:=` / typed-local / param / captures but NOT the `::` declaration form.

- ast: `ConstDecl`/`FnDecl` carry `is_raw` + `name_span` threaded from the parser
  (parseConstBinding / parseFnDecl, all call sites incl. struct/impl methods).
- semantic_diagnostics: reject a bare reserved spelling at EVERY declaration-name
  site — const, function (incl. struct/impl methods), struct/enum/union/error-set,
  protocol, foreign-class, ufcs alias, namespaced/library/c-import name. Backtick
  (`is_raw`) and the compiler's `#builtin` definition (`string :: []u8 #builtin`)
  are the only exemptions; a value whose node is itself a named decl defers to
  that node's own check.
- c_import: synthesized foreign fn_decls are `is_raw = true`, so a C function
  whose own name collides with a reserved spelling (`int s2(int);`) imports and
  bare-calls unedited.
- lower: scope the `.type_expr`→`.identifier` call rewrite to a callee FnDecl of
  RAW provenance (`is_raw`) — only a backtick / `#import c` foreign fn can carry a
  reserved-name spelling, so a non-raw match never gets rewritten.
- examples: 0153 (positive — backtick `::` const + fn, bare + tick call), 1140
  (negative — bare `::` const + fn rejected).
- docs: specs.md + readme.md state the backtick is required at every binding site
  including `::` const / function / type declarations; issue 0089 banner updated.
2026-06-04 19:16:37 +03:00
agra
640f59dc54 feat(lang): backtick raw identifier in every binding form + raw-not-a-type + foreign reserved-name fn bare-call [F0.6]
Completes the issue-0089 backtick raw-identifier / `#import c` exemption
across all remaining identifier positions and closes three boundary gaps
the F0.6 review found.

1. Exhaustive raw-binding coverage. The `is_raw` bit now threads through
   `ast.Identifier` and EVERY binding/capture form — `IfExpr`/`WhileExpr`
   optional bindings, `ForExpr` capture + index, `MatchArm` capture,
   `CatchExpr`/`OnFailStmt` tag bindings, `DestructureDecl` per-name, and
   the protocol-default-body / foreign-class method param lists — not just
   `var_decl`/`param`. `UnknownTypeChecker` skips the reserved-name check at
   each arm when raw, so a backtick works in every identifier position while
   a bare reserved spelling still errors (issue 0076 preserved).

2. Raw identifier is never a type. `parseTypeExpr`'s atom rejects a raw
   identifier in type position (`x : `s2 = 1`, `List(`s2)`) with an accurate
   diagnostic instead of silently type-classifying it.

3. Reserved-name function bare-callable. A bare `s2(4)` parses its callee as
   a `.type_expr` (reserved spelling); `lowerCall` now rewrites a type_expr
   callee to an identifier when a function of that name is in scope, so a
   backtick-declared sx fn and a `#import c` foreign fn whose C name collides
   with a reserved type spelling both resolve by their bare name.
   (`TypeName(val)` is not a cast, so there is no ambiguity.)

Tests: examples/0152 (every control-flow/capture form + bare ref/call/member
access), examples/1054 (catch/onfail tag bindings), examples/1139 (raw in
type position rejected), examples/1220 extended (foreign reserved-name
function bare-call). 0076 negatives 1119/1121/1122/1123/1124/1125 stay green.
Gate: zig build + zig build test + 422 examples pass. specs.md + readme.md
updated; issues/0089 RESOLVED banner refreshed.
2026-06-04 18:31:08 +03:00
agra
0dbdc530ba feat(lang): backtick raw-identifier escape + #import c foreign-name exemption [F0.6]
Reserved type-name spellings (s1, s2, u8, …) can now be used as value
identifiers two ways, resolving issue 0089:

1. Backtick raw identifier: a leading backtick (`s2) lexes to an
   .identifier token carrying a new Token.is_raw flag, with the backtick
   excluded from the text. A raw identifier is never type-classified — the
   parser skips Type.fromName for it — so it is always a value identifier.
   The flag threads to VarDecl.is_raw / Param.is_raw at binding sites, and
   the reserved-type-name check (UnknownTypeChecker) skips raw bindings.
   Because the token tag stays .identifier, the escape works in every
   position (local, global, param, field, fn name, struct member, later
   reference) with no per-site parser change.

2. #import c exemption: c_import.zig synthesizes foreign decls with
   Param.is_raw = true, so generated C param names that collide with
   reserved type names (s1, s2) import unedited.

A bare reserved-name binding in sx still errors (issue 0076 preserved):
the is_raw-gated skip only fires for backtick / foreign names, and a raw
binding's address-of / autoref lowering stays correct because every
occurrence is an .identifier, never a .type_expr.

Tests: examples/0151 (backtick, every position),
examples/1220 (foreign exemption, compiled+run), lexer unit tests.
1119 (bare-binding rejection) stays green. specs.md + readme.md updated.
2026-06-04 17:40:42 +03:00
agra
efc09699e8 fix(ir): value-param type functions + range-checked dim/lane fold (0083, 0087)
Two remaining siblings in F0.4's comptime-int path.

1. Type-returning function with a value param used as a TYPE annotation
   (`b : Make(N, s64)` where `Make :: ($K: u32, $T: Type) -> Type`):
   - `isValueParamPosition` (semantic_diagnostics) now also skips a value
     param of a `fn_ast_map` type-returning function, so `N` is not walked
     as the type name "N" ("unknown type 'N'").
   - `resolveParameterizedWithBindings` routes a type-returning-function
     name to `instantiateTypeFunction` (the `.call` path already did).
   - `instantiateTypeFunction` resolves a general return-type expression
     (`return [K]T`) with bindings active — not just struct/union returns.
   `Make(N, s64)`, `Make(M + 1, s64)`, `Make(3, s64)` all resolve to one
   `[3]s64`.

2. Oversized dim/lane fold panicked the compiler (0087): an array dim /
   Vector lane folded to a valid i64 (5e9) then narrowed to u32 with an
   unchecked `@intCast`. New single gate `program_index.foldDimU32` folds
   via `evalConstIntExpr` then range-checks `[min, maxInt(u32)]`; the three
   narrowing sites (resolveArrayLen stateful + stateless, resolveVectorLane)
   all route through it and emit a clean diagnostic + halt instead of
   panicking. Value-param args stay i64 until used as a dim/lane, where the
   same gate checks them.

Regressions: examples/0208 (value-param type function), examples/1130
(oversized array dim clean halt), examples/1503 (oversized Vector lane
clean halt). Marks issue 0087 RESOLVED.

Gate: zig build, zig build test, bash tests/run_examples.sh — 398 passed,
0 failed, 0 timed out.
2026-06-04 12:13:45 +03:00
agra
a491a1bf73 fix(ir): route every comptime-int through the shared evaluator (0083)
Attempts 1–4 fixed the array-dimension paths but the same length-0
fabrication class survived on every other site that resolves a
compile-time integer. Unify them all on the single shared
`program_index.evalConstIntExpr` so they cannot diverge:

- All three Vector lane resolvers (resolveTypeCallWithBindings,
  resolveParameterizedWithBindings, resolveArrayLiteralType) and both
  generic value-param binders (instantiateGenericStruct,
  instantiateTypeFunction) hand-rolled an `else => 0` switch. A
  module-const lane `Vector(N, f32)` fabricated a 0-lane `<0 x float>`
  (LLVM "huge alignment" abort); a value-param `Vec(N, f32)` fabricated
  a 0 binding / wrong mangled name. They now fold through the shared
  evaluator and emit a clean diagnostic + `.unresolved` on a non-const
  operand (resolveVectorLane / resolveValueParamArg) — never 0.
- evalComptimeInt (inline-for bounds) delegated to the shared evaluator,
  so `inline for 0..M` / `0..(M+1)` fold like array dims. The `<pack>.len`
  leaf moved into the shared folder via a new `ctx.lookupPackLen`.
- The unknown-type semantic checker no longer walks a value-param
  position (`Vector(N, …)` / `Vec(N, …)`) as a type name (was reporting
  "unknown type 'N'").
- The parameterized-type-arg parser and the function-body lookahead
  (hasFnBodyAfterArrow) accept a const-EXPRESSION in a value position, so
  `Vector(M + 1, f32)` and `[M + 1]T` parse as a return type too (the
  latter a pre-existing array-dim sibling that the same heuristic broke).

Regressions: examples/1501 (named-const + const-expr lane, direct +
alias, 3/4-lane reads), 1502 (runtime lane clean-halts, exit 1, no LLVM
crash), 0207 (Vec(N)/Vec(M+1) == Vec(3) instantiation), 0610 (inline-for
const bounds). Shared-evaluator unit test extended with the pack-len arm.

zig build && zig build test && bash tests/run_examples.sh: 395 passed,
0 failed.
2026-06-04 11:32:25 +03:00
agra
6433eb6155 fix(diagnostics): point reserved-type-name binding errors at the binding (issue 0076)
The reserved-type-name binding diagnostic fired correctly but underlined the
enclosing statement / if / while / for / match / protocol / #objc_class block
because every binding-name check reused the parent `node.span`.

Thread each binding name's own span through the AST and parser, and pass it to
`checkBindingNames`:

- ast: add name spans to VarDecl, DestructureDecl, If/WhileExpr, ForExpr
  (capture + index), MatchArm, Catch/OnFailStmt, Protocol/ForeignMethodDecl.
- parser: populate each span at the binding site from the name token's loc;
  destructure reuses each target identifier's own span.
- semantic_diagnostics: every checkBindingName call now passes the binding's
  own span — no site falls back to node.span. fn/lambda params already used
  Param.name_span.

Carets now land on the offending identifier itself. New regression
examples/1125 asserts the protocol default-body and sx-defined #objc_class
method param spans; 0125/1119-1124 expected updated to the precise carets.
2026-06-03 22:06:56 +03:00
agra
fcc76b9391 fix(diagnostics): make reserved-type-name binding check exhaustive (issue 0076)
The reserved/builtin-type-name binding diagnostic was a hand-walked subset
of binding-bearing AST nodes with a silent `else => {}`, so each review
found another syntactic binding form that bypassed it and hit the original
LLVM verifier abort: destructure names (`s2, x := …`), `impl` method
params/locals, and `if` / `while` / `for` / match-arm / `catch` / `onfail`
captures.

Rewrite `checkBindingNames` (src/ir/semantic_diagnostics.zig) as an
EXHAUSTIVE `switch` over every `Node.Data` tag with NO `else` arm — a future
binding-bearing node type now fails to compile until it is handled here, so
coverage is enforced by the compiler instead of a hand-maintained list. The
check stays in the pre-lowering semantic pass rather than moving to the
`Scope.put` scope-registration choke point: lowering is lazy, so an
uncalled function's bindings never reach `Scope.put`, yet they must still be
rejected at their declaration (e.g. the never-called `takes_u8` in 1119).
No lowering special-case; `lower.zig` unchanged.

Regression tests (fail-before: LLVM abort or silent accept → pass-after:
clean diagnostic, exit 1):
- 1121 control-flow: destructure, if/while bindings, for capture+index,
  match-arm capture
- 1122 impl-block method: reserved param AND reserved local
- 1123 catch + onfail tag bindings
- 1124 destructure name reserved in an imported module
Existing 0125 / 1119 / 0135 / 1120 tests kept; full suite 368 passed.
2026-06-03 20:09:46 +03:00
agra
df6e830bec fix(diagnostics): reject reserved type-name bindings in every module (issue 0077)
The issue-0076 reserved-type-name binding diagnostic only ran over main-file
decls, so an imported module (or the stdlib) could still declare `s2 := ...`
and reach lowering, where the address-of family loads the whole aggregate and
passes it by value to a `ptr` param — LLVM verifier abort.

Extend coverage to every compiled module: a dedicated `checkBindingNames` walk
(in semantic_diagnostics.zig) visits every var/`:=`/typed-local binding name and
function/lambda/struct-method parameter at any depth, with NO main-file filter,
descending the `namespace_decl` that a `mod :: #import` wraps so imported-module
decls are reached. It tracks each module's source_file (save/restore per node)
so the diagnostic renders against the imported module's text. Rejection still
defers to the parser's `Type.fromName` classifier; the unknown-type check (0064)
stays main-file-only. No lowering special-case; `.identifier`-only address-of
paths are unchanged.

Stdlib audit: the only reserved-name bindings under library/ were two `u1`
locals in ui/renderer.sx (UV coords) — renamed to u_min/u_max/v_min/v_max.

Regression test: examples/1120-diagnostics-imported-reserved-type-name.sx (+
companion mod.sx) — an imported `s2 := ...` now emits the clean diagnostic at
the import's declaration site (exit 1), not an LLVM abort.

Resolves issues 0076 (coverage extension) and 0077.
2026-06-03 19:32:49 +03:00
agra
f49a49cd07 fix(diagnostics): reject reserved/builtin type names used as identifiers (issue 0076)
A value binding (local/global `var` or a parameter) spelled as a
reserved/builtin type name parses as a `.type_expr` rather than an
`.identifier` (parser.zig, via `Type.fromName`), so the address-of
family in lower.zig never saw a scoped local and mis-lowered it —
loading the aggregate and passing it by value to a `ptr` parameter
(LLVM verifier abort, or a silent `*self`-mutation-losing copy).

Add a declaration-site diagnostic in semantic_diagnostics.zig
(`UnknownTypeChecker.checkBindingName`): reject any parameter name or
`var` binding name (`:=` / typed-local / global forms) whose spelling
collides with a reserved type name. `isReservedTypeName` defers to the
parser's own classifier (`types.Type.fromName`) so the rejected set
never drifts from the set that would parse as a type — the named
builtins (bool/string/void/f32/f64/usize/isize/Any) and `[su]N` over
sx's 1-64 range. Bare value names (`s`, `self`, `index`) are untouched.
No lowering special-case; the `.identifier`-only address-of paths are
correct once type-shaped names can never be bound. The rejected
attempt-1 `bareVarName` approach was never landed.

Tests:
- 0125-types-type-named-var-rejected: `:=` form (s2) rejected
  (repurposed from the old test that asserted the now-illegal behavior).
- 1119-diagnostics-reserved-type-name-as-identifier: parameter (u8),
  typed-local (s64, bool), `:=` (string) forms rejected.
- 0135-types-self-streaming-nonreserved: positive — `*self` streaming
  with non-reserved names accumulates correctly via both call styles.
- 0904-optionals: renamed incidental locals s1/s2 -> filled/empty.
2026-06-03 19:00:39 +03:00
agra
877014578e fix(ir): value const used as a type must not satisfy unknown-type check (issue 0068)
The A2.4 unknown-type pass (semantic_diagnostics) added EVERY const_decl name to
its declared-type-name set. A value const (`NotAType :: 123`) thus satisfied
reportIfUnknownType, so `v: NotAType` was not flagged; lowering then hit
TypeResolver.resolveNamed's empty-struct-stub fallback and fabricated
`NotAType{}` (the program ran, printing it).

Fix: collectDeclaredTypeNames and harvestScopeDecls now gate the const-name-add
on a new constValueIntroducesType — true only when the value introduces a type
(declarations: struct/enum/union/error; type-expression aliases: type_expr,
pointer/many-pointer/slice/optional/array/function/closure/tuple, parameterized).
`.identifier` / `.call` aliases are intentionally excluded: the scan registers
the type-valued ones into ProgramIndex.type_alias_map / the TypeTable (both
queried separately by the pass), so a value-RHS alias is correctly left out and
flagged, while a type-RHS alias stays covered by the canonical facts.

Regression: examples/1117-diagnostics-value-const-as-type-rejected.sx (exit 1).
Issue-0064 regressions 1111-1116 and the 0115 aliases stay green. Gate: zig
build, zig build test, run_examples 352/0.
2026-06-02 16:33:38 +03:00
agra
8ff24472c9 refactor(ir): extract unknown-type diagnostic pass into semantic_diagnostics (A2.4)
Moves the issue-0064 unknown-type pass (checkUnknownTypeNames + 11 helpers:
collectDeclaredTypeNames, harvestScopeDecls, checkStructFieldTypes,
checkFnSignatureTypes, checkScope, walkBodyTypes, checkCastTarget,
checkTypeNodeForUnknown, reportIfUnknownType, isBuiltinTypeName, isIdentLike)
out of Lowering into a new src/ir/semantic_diagnostics.zig (UnknownTypeChecker).

The checker holds borrowed references (alloc, *DiagnosticList, *TypeTable,
*ProgramIndex, main_file) — not *Lowering — and queries the canonical facts:
declared top-level names from ProgramIndex, primitives from
TypeResolver.resolvePrimitive, registered concrete types from the TypeTable.
The AST decl/scope walk stays (it collects LOCAL type decls, which ProgramIndex
doesn't track — a per-pass scope need, not a parallel authoritative list).

Lowering.lowerRoot builds the checker only when diagnostics are active and runs
it; the 12 functions are deleted from lower.zig. Barrel-wired in ir.zig.
Example snapshots (issue-0064 regressions 1111-1115) are the guard, matching the
checkErrorFlow precedent (no .test.zig).

Phase A2 complete. Gate: zig build, zig build test, run_examples 351/0.
2026-06-02 16:12:28 +03:00