fix(bootstrap): implement collection for-in lowering
- Export typeToTypeExpr from sema and preserve generic type args - Derive loop variable type from collection element type in sema - Substitute generic struct type params on field access - Add getCollectionElementTypeExpr helper in hir_lower - Replace placeholder collection for-in lowering - Add Array/Iter lowering: Array_Iter_T / Iter_HasNext_T / Iter_Next_T - Add Channel lowering: Channel_Recv_Ok_T loop - Register loop variable in varTypeExprs before body lowering Fixes _test_forin_stdlib, _test_forin_channel, _test_generic_trait, _test_import, _test_mono
This commit is contained in:
@@ -0,0 +1,378 @@
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# Fix `for ... in` Iterator Lowering — Implementation Plan
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> **For agentic workers:** REQUIRED SUB-SKILL: Use `superpowers:subagent-driven-development` (recommended) or `superpowers:executing-plans` to implement this plan task-by-task. Steps use checkbox (`- [ ]`) syntax for tracking.
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**Goal:** Replace the placeholder collection `for ... in` lowering in the bootstrap compiler with correct Array/Iter and Channel lowerings, fixing `_test_forin_stdlib`, `_test_forin_channel`, `_test_generic_trait`, `_test_import`, and `_test_mono`.
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**Architecture:** Determine the concrete element type in sema and register the loop variable with it; in HIR lowering emit explicit alloca/store/while nodes that call monomorphized iterator helpers (`Array_Iter_T`, `Iter_HasNext_T`, `Iter_Next_T`) for arrays and `Channel_Recv_Ok_T` for channels. Also fix generic struct field access so direct field mutations on `Array<int>` work.
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**Tech Stack:** Nim (bootstrap compiler), Bux integration tests.
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---
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## Task 1: Export and Fix `typeToTypeExpr`
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**Files:**
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- Modify: `bootstrap/sema.nim:140-157`
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- [ ] **Step 1.1: Export the helper and preserve type args for named types**
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Find:
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```nim
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proc typeToTypeExpr(t: Type): TypeExpr =
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```
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Change the signature to `proc typeToTypeExpr*(t: Type): TypeExpr =` and update the `tkNamed` branch:
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```nim
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of tkNamed:
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var args: seq[TypeExpr] = @[]
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for a in t.inner:
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args.add(typeToTypeExpr(a))
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return TypeExpr(kind: tekNamed, typeName: t.name, typeArgs: args)
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```
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This lets HIR lowering round-trip a resolved concrete `Type` back to a `TypeExpr` that can be mangled into the correct struct instance name (e.g. `Array<int>` → `Array_int`).
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---
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## Task 2: Derive Loop-Variable Type in Sema
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**Files:**
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- Modify: `bootstrap/sema.nim:1503-1515`
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- [ ] **Step 2.1: Set the loop variable type from the collection's element type**
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Find the `of skFor:` branch and update it so `iterTyp` is the collection element type:
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```nim
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of skFor:
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let iterExpr = stmt.stmtForIter
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let collType = sema.checkExpr(iterExpr, scope)
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var forScope = newScope(scope)
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var iterTyp = makeUnknown()
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if iterExpr.kind == ekRange:
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iterTyp = sema.checkExpr(iterExpr.exprRangeLo, scope)
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elif collType.kind == tkNamed and collType.inner.len > 0:
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iterTyp = collType.inner[0]
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elif collType.isPointer and collType.inner.len > 0 and collType.inner[0].kind == tkNamed and collType.inner[0].inner.len > 0:
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iterTyp = collType.inner[0].inner[0]
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let iterSym = Symbol(kind: skVar, name: stmt.stmtForVar, typ: iterTyp, isMutable: true)
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discard forScope.define(iterSym)
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discard sema.checkStmt(Stmt(kind: skExpr, loc: stmt.stmtForBody.loc, stmtExpr: Expr(kind: ekBlock, loc: stmt.stmtForBody.loc, exprBlock: stmt.stmtForBody)), forScope)
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return makeVoid()
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```
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---
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## Task 3: Substitute Generic Struct Type Parameters on Field Access
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**Files:**
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- Modify: `bootstrap/sema.nim:1269-1273` and `bootstrap/sema.nim:180-215`
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- [ ] **Step 3.1: Build substitution map in `ekField` for struct fields**
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In the `dkStruct` branch of `ekField`, build a substitution map from the object's concrete type arguments before resolving the field type:
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```nim
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if sym.decl.kind == dkStruct:
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var subst = initTable[string, Type]()
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for i, tp in sym.decl.declStructTypeParams:
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if i < objType.inner.len:
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subst[tp.name] = objType.inner[i]
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for f in sym.decl.declStructFields:
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if f.name == expr.exprFieldName:
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return sema.substituteTypeInType(sema.resolveType(f.ftype), subst)
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sema.emitError(expr.loc, &"struct '{objType.name}' has no field '{expr.exprFieldName}'")
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```
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- [ ] **Step 3.2: Make `substituteTypeInType` handle named type-parameter names**
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In `substituteTypeInType`, add a lookup for `tkNamed` names that are type-parameter names:
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```nim
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of tkNamed:
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if subst.hasKey(t.name):
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return subst[t.name]
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if t.inner.len > 0:
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var args: seq[Type] = @[]
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for a in t.inner:
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args.add(sema.substituteTypeInType(a, subst))
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return Type(kind: tkNamed, name: t.name, inner: args)
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return t
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```
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---
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## Task 4: Add `getCollectionElementTypeExpr` Helper in `hir_lower.nim`
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**Files:**
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- Modify: `bootstrap/hir_lower.nim` (after `resolveExprType` definition)
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- [ ] **Step 4.1: Add the helper**
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```nim
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proc getCollectionElementTypeExpr(ctx: var LowerCtx, expr: Expr): TypeExpr =
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## Return the element TypeExpr of a collection expression (Array<T>, Iter<T>, Channel<T>).
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## For identifiers we can use the declared TypeExpr directly; for other expressions we
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## fall back to the resolved concrete Type.
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case expr.kind
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of ekIdent:
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if ctx.varTypeExprs.hasKey(expr.exprIdent):
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let te = ctx.varTypeExprs[expr.exprIdent]
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if te.kind == tekNamed and te.typeArgs.len > 0:
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return te.typeArgs[0]
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if te.kind in {tekPointer, tekRef, tekMutRef} and te.pointerPointee.kind == tekNamed and te.pointerPointee.typeArgs.len > 0:
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return te.pointerPointee.typeArgs[0]
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else:
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discard
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let t = ctx.resolveExprType(expr)
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if t.kind == tkNamed and t.inner.len > 0:
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return typeToTypeExpr(t.inner[0])
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if t.isPointer and t.inner.len > 0 and t.inner[0].kind == tkNamed and t.inner[0].inner.len > 0:
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return typeToTypeExpr(t.inner[0].inner[0])
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return TypeExpr(kind: tekNamed, typeName: "unknown")
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```
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---
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## Task 5: Implement Collection `for ... in` Lowering
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**Files:**
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- Modify: `bootstrap/hir_lower.nim` (replace the placeholder at lines 1339-1342)
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- [ ] **Step 5.1: Replace the placeholder collection lowering**
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Find:
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```nim
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# Generic iterator for loop (simplified - just infinite loop for now)
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let loweredIter = ctx.lowerExpr(iterExpr)
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let loweredBody = ctx.lowerBlock(body)
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return ctx.flushPending(HirNode(kind: hLoop, loopBody: loweredBody, typ: makeVoid(), loc: loc))
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```
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Replace with:
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```nim
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# Collection-based for: for x in collection { body }
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let collType = ctx.resolveExprType(iterExpr)
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let elemTypeExpr = ctx.getCollectionElementTypeExpr(iterExpr)
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let elemType = ctx.resolveTypeExpr(elemTypeExpr)
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# Resolve the collection type to its mangled struct instance (e.g. Array<int> -> Array_int).
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let collTypeMangled = substituteType(ctx, typeToTypeExpr(collType), ctx.typeSubst)
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let isChannel = collType.kind == tkNamed and collType.name.startsWith("Channel")
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if isChannel:
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# Channel lowering:
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# alloca x
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# while (true) {
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# if (!Channel_Recv_Ok_T(&ch, &x)) break;
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# body
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# }
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let recvOkName = ctx.generateMethodInstance("Channel_Recv_Ok", @[elemTypeExpr])
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let xAlloca = hirAlloca(varName, elemType, loc)
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let xVar = hirVar(varName, elemType, loc)
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ctx.varTypeExprs[varName] = elemTypeExpr
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let chAddr = HirNode(kind: hUnary, unaryOp: tkAmp, unaryOperand: ctx.lowerExpr(iterExpr),
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typ: makePointer(collTypeMangled), loc: loc)
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let xAddr = HirNode(kind: hUnary, unaryOp: tkAmp, unaryOperand: xVar,
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typ: makePointer(elemType), loc: loc)
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let recvOkCall = hirCall(recvOkName, @[chAddr, xAddr], makeBool(), loc)
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let notRecvOk = HirNode(kind: hUnary, unaryOp: tkBang, unaryOperand: recvOkCall,
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typ: makeBool(), loc: loc)
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let breakNode = HirNode(kind: hBreak, loc: loc)
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let ifNode = HirNode(kind: hIf, ifCond: notRecvOk, ifThen: breakNode, ifElse: nil,
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typ: makeVoid(), loc: loc)
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let loweredBody = ctx.lowerBlock(body)
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var whileBodyStmts: seq[HirNode] = @[]
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whileBodyStmts.add(xAlloca)
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whileBodyStmts.add(ifNode)
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if loweredBody != nil:
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whileBodyStmts.add(loweredBody)
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let whileBody = hirBlock(whileBodyStmts, nil, makeVoid(), loc)
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let trueLit = hirLit(Token(kind: tkBoolLiteral, text: "true", loc: loc), makeBool(), loc)
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let whileNode = HirNode(kind: hWhile, whileCond: trueLit, whileBody: whileBody,
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typ: makeVoid(), loc: loc)
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let forBlock = hirBlock(@[whileNode], nil, makeVoid(), loc, isScope = true)
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return ctx.flushPending(forBlock)
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# Array / Iter lowering:
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# alloca __iter
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# __iter = Array_Iter_T(&collection);
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# while (Iter_HasNext_T(&__iter)) {
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# alloca x
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# x = Iter_Next_T(&__iter);
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# body
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# }
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let iterFuncName = ctx.generateMethodInstance("Array_Iter", @[elemTypeExpr])
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let hasNextFuncName = ctx.generateMethodInstance("Iter_HasNext", @[elemTypeExpr])
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let nextFuncName = ctx.generateMethodInstance("Iter_Next", @[elemTypeExpr])
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# Ensure Iter<T> struct instance exists and resolve its mangled name.
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let iterType = substituteType(ctx, TypeExpr(kind: tekNamed, typeName: "Iter", typeArgs: @[elemTypeExpr]), ctx.typeSubst)
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let iterVarName = "__iter_" & varName & "_" & $ctx.varCounter
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inc ctx.varCounter
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# Build collection pointer. If the collection is not a simple identifier, spill to a temp.
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var preStmts: seq[HirNode] = @[]
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var collPtr: HirNode = nil
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if iterExpr.kind == ekIdent:
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let collVar = hirVar(iterExpr.exprIdent, collTypeMangled, loc)
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collPtr = HirNode(kind: hUnary, unaryOp: tkAmp, unaryOperand: collVar,
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typ: makePointer(collTypeMangled), loc: loc)
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else:
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let collAllocaName = ctx.freshName()
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let collAlloca = hirAlloca(collAllocaName, collTypeMangled, loc)
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let collVarPtr = hirVar(collAllocaName, makePointer(collTypeMangled), loc)
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let collValue = ctx.lowerExpr(iterExpr)
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let collStore = hirStore(collVarPtr, collValue, loc)
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preStmts.add(collAlloca)
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preStmts.add(collStore)
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collPtr = HirNode(kind: hUnary, unaryOp: tkAmp,
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unaryOperand: hirVar(collAllocaName, collTypeMangled, loc),
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typ: makePointer(collTypeMangled), loc: loc)
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let iterAlloca = hirAlloca(iterVarName, iterType, loc)
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let iterVarPtr = hirVar(iterVarName, makePointer(iterType), loc)
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let iterInitCall = hirCall(iterFuncName, @[collPtr], iterType, loc)
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let iterStore = hirStore(iterVarPtr, iterInitCall, loc)
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preStmts.add(iterAlloca)
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preStmts.add(iterStore)
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# while condition: Iter_HasNext_T(&__iter)
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let iterAddr = HirNode(kind: hUnary, unaryOp: tkAmp, unaryOperand: hirVar(iterVarName, iterType, loc),
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typ: makePointer(iterType), loc: loc)
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let condCall = hirCall(hasNextFuncName, @[iterAddr], makeBool(), loc)
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# loop body: alloca x; x = Iter_Next_T(&__iter); body
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let xAlloca = hirAlloca(varName, elemType, loc)
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let xVarPtr = hirVar(varName, makePointer(elemType), loc)
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let iterAddr2 = HirNode(kind: hUnary, unaryOp: tkAmp, unaryOperand: hirVar(iterVarName, iterType, loc),
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typ: makePointer(iterType), loc: loc)
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let nextCall = hirCall(nextFuncName, @[iterAddr2], elemType, loc)
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let xStore = hirStore(xVarPtr, nextCall, loc)
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ctx.varTypeExprs[varName] = elemTypeExpr
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let loweredBody = ctx.lowerBlock(body)
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var bodyStmts: seq[HirNode] = @[]
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bodyStmts.add(xAlloca)
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bodyStmts.add(xStore)
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if loweredBody != nil:
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bodyStmts.add(loweredBody)
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let whileBody = hirBlock(bodyStmts, nil, makeVoid(), loc)
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let whileNode = HirNode(kind: hWhile, whileCond: condCall, whileBody: whileBody,
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typ: makeVoid(), loc: loc)
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var blockStmts = preStmts
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blockStmts.add(whileNode)
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let forBlock = hirBlock(blockStmts, nil, makeVoid(), loc, isScope = true)
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return ctx.flushPending(forBlock)
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```
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---
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## Task 6: Build and Verify
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**Files:**
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- Test: `_test_forin_stdlib`, `_test_forin_channel`, `_test_generic_trait`, `_test_import`, `_test_mono`
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- [ ] **Step 6.1: Rebuild the bootstrap compiler**
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Run:
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```bash
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cd /home/ziko/z-git/bux/bux
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make build
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```
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Expected: build succeeds.
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- [ ] **Step 6.2: Run the five target integration tests**
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Run:
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```bash
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cd /home/ziko/z-git/bux/bux/_test_forin_stdlib && /home/ziko/z-git/bux/bux/buxc run
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cd /home/ziko/z-git/bux/bux/_test_forin_channel && /home/ziko/z-git/bux/bux/buxc run
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cd /home/ziko/z-git/bux/bux/_test_generic_trait && /home/ziko/z-git/bux/bux/buxc run
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cd /home/ziko/z-git/bux/bux/_test_import && /home/ziko/z-git/bux/bux/buxc run
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cd /home/ziko/z-git/bux/bux/_test_mono && /home/ziko/z-git/bux/bux/buxc run
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```
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Expected: all compile and run; programs that return the sum (`_test_generic_trait`, `_test_import`, `_test_mono`) exit with code 60, which is their expected return value.
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- [ ] **Step 6.3: Run `make test`**
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|
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```bash
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cd /home/ziko/z-git/bux/bux
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make test
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```
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Expected: no new failures.
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- [ ] **Step 6.4: Run `make selfhost-loop`**
|
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|
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```bash
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cd /home/ziko/z-git/bux/bux
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make selfhost-loop
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```
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Expected: C output and stripped ELF binary remain identical.
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---
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## Task 7: Commit
|
||||
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- [ ] **Step 7.1: Commit the changes**
|
||||
|
||||
```bash
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cd /home/ziko/z-git/bux/bux
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git add bootstrap/sema.nim bootstrap/hir_lower.nim
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git commit -m "fix(bootstrap): implement collection for-in lowering
|
||||
|
||||
- Export typeToTypeExpr from sema and preserve generic type args
|
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- Derive loop variable type from collection element type in sema
|
||||
- Substitute generic struct type params on field access
|
||||
- Add getCollectionElementTypeExpr helper in hir_lower
|
||||
- Replace placeholder collection for-in lowering
|
||||
- Add Array/Iter lowering: Array_Iter_T / Iter_HasNext_T / Iter_Next_T
|
||||
- Add Channel lowering: Channel_Recv_Ok_T loop
|
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- Register loop variable in varTypeExprs before body lowering
|
||||
|
||||
Fixes _test_forin_stdlib, _test_forin_channel, _test_generic_trait, _test_import, _test_mono"
|
||||
```
|
||||
|
||||
---
|
||||
|
||||
## Spec Coverage Check
|
||||
|
||||
| Spec Requirement | Plan Task |
|
||||
|---|---|
|
||||
| Export and fix `typeToTypeExpr` | Task 1 |
|
||||
| Derive loop variable type in sema | Task 2 |
|
||||
| Substitute generic struct type params on field access | Task 3 |
|
||||
| Add `getCollectionElementTypeExpr` helper | Task 4 |
|
||||
| Array/Iter collection lowering | Task 5 |
|
||||
| Channel collection lowering | Task 5 |
|
||||
| Loop variable declaration and scope registration | Task 5 |
|
||||
| Target tests pass | Task 6 |
|
||||
| No regressions | Task 6 |
|
||||
|
||||
## Placeholder Scan
|
||||
|
||||
- No TBD/TODO/fill-in-later steps.
|
||||
- Every code block contains the exact code to insert.
|
||||
- Every command contains the exact path and expected outcome.
|
||||
@@ -0,0 +1,172 @@
|
||||
# Fix `for ... in` Iterator Lowering in Bootstrap
|
||||
|
||||
> **Date:** 2026-06-14
|
||||
> **Status:** Approved
|
||||
> **Scope:** Bootstrap compiler (`bootstrap/hir_lower.nim`) — `for <var> in <collection>` loops
|
||||
|
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## 1. Problem Statement
|
||||
|
||||
The `for ... in` collection iterator is already parsed and sema-accepted, but the HIR→C lowering produces broken code for concrete generic collections such as `Array<int>` or `Channel<int>`.
|
||||
|
||||
Five integration tests fail because of this:
|
||||
|
||||
- `_test_forin_stdlib`: C compilation error `‘x’ undeclared` inside `Main`.
|
||||
- `_test_forin_channel`: C compilation error `‘msg’ undeclared` inside `Main`.
|
||||
- `_test_generic_trait`: sema error `cannot assign float32 to int at 12:9` — the loop variable `x` is typed as `float32` instead of `int`.
|
||||
- `_test_import`: sema error `cannot assign float32 to int at 15:9` — same issue.
|
||||
- `_test_mono`: sema error `cannot assign float32 to int at 38:9` — same issue.
|
||||
|
||||
Two independent bugs are at play:
|
||||
|
||||
1. **Missing C declaration:** the loop variable is not emitted as a local variable in the generated C function.
|
||||
2. **Wrong loop-variable type:** generic `Iter_Next_T` returns an unsubstituted type parameter `T`, which sema treats as `float32` by default.
|
||||
|
||||
## 2. Goals
|
||||
|
||||
1. Make `_test_forin_stdlib` pass.
|
||||
2. Make `_test_forin_channel` pass.
|
||||
3. Make `_test_generic_trait`, `_test_import`, and `_test_mono` pass (or at least no longer fail with the `float32` loop-variable error).
|
||||
4. Keep the fix minimal and confined to the bootstrap compiler.
|
||||
5. Ensure `make test` and `make selfhost-loop` continue to pass.
|
||||
|
||||
## 3. Non-Goals
|
||||
|
||||
1. Rewriting the `apps/` example applications (excluded per user request).
|
||||
2. Adding new language features such as `break`/`continue` in loops or iterator traits.
|
||||
3. Changing the selfhost compiler (`src/*.bux`) unless required for selfhost-loop parity.
|
||||
4. Fixing the unrelated `_test_slice` C typedef bug (tracked separately).
|
||||
5. Implementing full Destructors / Drop trait (next roadmap milestone after stabilization).
|
||||
|
||||
## 4. Background: How `for ... in` Is Lowered
|
||||
|
||||
The parser produces `stmtForIn(ident, expr, body)`.
|
||||
|
||||
Sema checks the collection expression and infers the loop-variable type from it.
|
||||
|
||||
HIR lowering currently desugars the loop to a placeholder infinite `hLoop` that ignores the iterator expression and never declares the loop variable.
|
||||
|
||||
The intended lowering depends on the collection type:
|
||||
|
||||
- **Array / Iter collections** (from `lib/Iter.bux`):
|
||||
```bux
|
||||
let __iter = Array_Iter_T(&collection);
|
||||
while (Iter_HasNext_T(&__iter)) {
|
||||
let x = Iter_Next_T(&__iter);
|
||||
// body
|
||||
}
|
||||
```
|
||||
- **Channel collections** (from `lib/Channel.bux`):
|
||||
```bux
|
||||
var x: T;
|
||||
while (true) {
|
||||
if (!Channel_Recv_Ok_T(&ch, &x)) { break; }
|
||||
// body
|
||||
}
|
||||
```
|
||||
|
||||
## 5. Investigation Plan
|
||||
|
||||
1. Read `_test_forin_stdlib/src/Main.bux`, `_test_forin_channel/src/Main.bux`, `_test_generic_trait/src/Main.bux`.
|
||||
2. Locate `stmtForIn` handling in `bootstrap/hir_lower.nim`.
|
||||
3. Verify how the iterator variable is introduced into HIR/C:
|
||||
- Is it registered in `ctx.varTypes` / `ctx.varTypeExprs`?
|
||||
- Is a `hirLet` emitted before the loop body?
|
||||
4. Verify how `Array_Iter_Next_T` is monomorphized:
|
||||
- Does the call get the `_int` suffix?
|
||||
- Does the returned `T` get substituted with `int`?
|
||||
5. Identify the minimal edit that fixes both symptoms.
|
||||
|
||||
## 6. Hypothesis
|
||||
|
||||
### 6.1 Missing Declaration
|
||||
|
||||
The lowering creates the loop body with references to the loop variable, but the declaration site is omitted or not added to the function's local-variable list. As a result, the C backend never emits `int x;`, causing the `undeclared identifier` error.
|
||||
|
||||
### 6.2 Wrong Type
|
||||
|
||||
When the collection is `Array<int>`, the lowering calls `Array_Iter_Next` (without `_int`) or calls a monomorphized `Array_Iter_Next_int` but assigns its result to a variable whose type was resolved from the generic signature (`T`). Because sema does not substitute `T` for the loop variable, the variable defaults to `float32`.
|
||||
|
||||
The fix is likely to:
|
||||
|
||||
- Explicitly declare the loop variable with the concrete element type derived from the collection type.
|
||||
- Ensure `Array_Iter` / `Array_Iter_HasNext` / `Array_Iter_Next` are monomorphized with the collection's type arguments.
|
||||
|
||||
## 7. Proposed Fix
|
||||
|
||||
The fix spans sema and HIR lowering:
|
||||
|
||||
1. **Sema fixes**:
|
||||
- In `skFor`, derive the loop-variable type from the collection's element type (`Array<T>` / `Channel<T>` inner type).
|
||||
- In `ekField` for structs, build a type-parameter substitution map from the object's concrete type args and apply it to the field type, so `arr.data` on `Array<int>` resolves to `*int`.
|
||||
- Fix `typeToTypeExpr` to preserve generic type arguments on named types.
|
||||
|
||||
2. **HIR lowering**:
|
||||
- Replace the placeholder `skFor` collection branch with real lowering that selects by collection type.
|
||||
- **Array / Iter collections**:
|
||||
- Extract element type from `Array<T>` or `Iter<T>`.
|
||||
- Generate or reuse `Iter_T` struct instance.
|
||||
- Generate function instances `Array_Iter_T`, `Iter_HasNext_T`, `Iter_Next_T`.
|
||||
- If the collection expression is not a simple identifier, spill it to a temporary `Array_T` variable first.
|
||||
- Emit `alloca __iter`, store `Array_Iter_T(&collection)`, then `while (Iter_HasNext_T(&__iter)) { let x = Iter_Next_T(&__iter); body }`.
|
||||
- Register `x` in `ctx.varTypeExprs` before lowering the body.
|
||||
- **Channel collections**:
|
||||
- Extract element type from `Channel<T>`.
|
||||
- Generate function instance `Channel_Recv_Ok_T`.
|
||||
- Emit `alloca x`, then `while (true) { if (!Channel_Recv_Ok_T(&ch, &x)) break; body }`.
|
||||
|
||||
## 8. Affected Files
|
||||
|
||||
| File | Expected Change |
|
||||
|------|-----------------|
|
||||
| `bootstrap/sema.nim` | Derive loop var type; substitute struct type params on field access; preserve type args in `typeToTypeExpr`. |
|
||||
| `bootstrap/hir_lower.nim` | Replace placeholder collection `skFor` lowering with Array/Iter and Channel lowerings. |
|
||||
| `_test_forin_stdlib/src/Main.bux` | No changes. |
|
||||
| `_test_forin_channel/src/Main.bux` | No changes. |
|
||||
| `_test_generic_trait/src/Main.bux` | No changes. |
|
||||
| `_test_import/src/Main.bux` | No changes. |
|
||||
| `_test_mono/src/Main.bux` | No changes. |
|
||||
|
||||
## 9. Testing Plan
|
||||
|
||||
### 9.1 Target Tests
|
||||
|
||||
```bash
|
||||
cd _test_forin_stdlib && /home/ziko/z-git/bux/bux/buxc run
|
||||
cd _test_forin_channel && /home/ziko/z-git/bux/bux/buxc run
|
||||
cd _test_generic_trait && /home/ziko/z-git/bux/bux/buxc run
|
||||
cd _test_import && /home/ziko/z-git/bux/bux/buxc run
|
||||
cd _test_mono && /home/ziko/z-git/bux/bux/buxc run
|
||||
```
|
||||
|
||||
Expected: all exit 0.
|
||||
|
||||
### 9.2 Regression Tests
|
||||
|
||||
```bash
|
||||
cd /home/ziko/z-git/bux/bux
|
||||
make test
|
||||
make selfhost-loop
|
||||
```
|
||||
|
||||
Expected: all pass / no changes in selfhost-loop output.
|
||||
|
||||
## 10. Success Criteria
|
||||
|
||||
- `_test_forin_stdlib` reports PASS.
|
||||
- `_test_forin_channel` reports PASS.
|
||||
- `_test_generic_trait`, `_test_import`, `_test_mono` no longer fail with the `float32` loop-variable error.
|
||||
- `make test` reports no new failures.
|
||||
- `make selfhost-loop` remains deterministic.
|
||||
|
||||
## 11. Risks & Mitigations
|
||||
|
||||
| Risk | Mitigation |
|
||||
|------|------------|
|
||||
| Fix changes loop lowering and breaks range-based `for i in 0..10` | Keep range-based path separate; only touch `stmtForIn` collection path. |
|
||||
| Same bug exists in selfhost compiler | Selfhost-loop will catch output differences; fix selfhost only if required. |
|
||||
| Root cause is deeper than loop lowering | Time-box investigation; report findings if not resolved quickly. |
|
||||
|
||||
## 12. Relation to Other Work
|
||||
|
||||
- Previous commit `06db492` fixed generic `operator []` resolution. This work continues generic-type propagation into iterator loops.
|
||||
- `_test_slice` has a separate C typedef bug and is out of scope for this task.
|
||||
Reference in New Issue
Block a user