{"body":"Teaches Forget to compile simple ForOf statements, where the init comprises of a \nvariable declaration with an identifier or destructure.","commit":{"shortRevision":"61462a43bc","authorEmail":"poteto@users.noreply.github.com","authoredAt":"2023-03-31T17:55:04-04:00","subject":"Add support for ForOf statements","authorName":"Lauren Tan","revision":"61462a43bc53de1d7a19d49f62bfe108a03cca45"},"patch":"diff --git a\/compiler\/forget\/src\/HIR\/BuildHIR.ts b\/compiler\/forget\/src\/HIR\/BuildHIR.ts\nindex 62e023b757..0095bc0443 100644\n--- a\/compiler\/forget\/src\/HIR\/BuildHIR.ts\n+++ b\/compiler\/forget\/src\/HIR\/BuildHIR.ts\n@@ -712,7 +712,83 @@ function lowerStatement(\n lowerStatement(builder, desugared.at(0)!);\n return;\n }\n- case \"ForOfStatement\":\n+ case \"ForOfStatement\": {\n+ const stmt = stmtPath as NodePath;\n+ const continuationBlock = builder.reserve(\"block\");\n+ const initBlock = builder.reserve(\"loop\");\n+\n+ const loopBlock = builder.enter(\"block\", (_blockId) => {\n+ return builder.loop(label, initBlock.id, continuationBlock.id, () => {\n+ lowerStatement(builder, stmt.get(\"body\"));\n+ return {\n+ kind: \"goto\",\n+ block: initBlock.id,\n+ variant: GotoVariant.Continue,\n+ id: makeInstructionId(0),\n+ };\n+ });\n+ });\n+\n+ const loc = stmt.node.loc ?? GeneratedSource;\n+ const value = lowerExpressionToTemporary(builder, stmt.get(\"right\"));\n+ builder.terminateWithContinuation(\n+ {\n+ kind: \"for-of\",\n+ loc,\n+ init: initBlock.id,\n+ loop: loopBlock,\n+ fallthrough: continuationBlock.id,\n+ id: makeInstructionId(0),\n+ },\n+ initBlock\n+ );\n+\n+ \/\/ The init of a ForOf statement is compound over a left (VariableDeclaration | LVal) and\n+ \/\/ right (Expression), so we synthesize a new InstrValue and assignment (potentially multiple\n+ \/\/ instructions when we handle other syntax like Patterns)\n+ const left = stmt.get(\"left\");\n+ const leftLoc = left.node.loc ?? GeneratedSource;\n+ let test: Place;\n+ if (left.isVariableDeclaration()) {\n+ const declarations = left.get(\"declarations\");\n+ invariant(\n+ declarations.length === 1,\n+ `Expected only one declaration in the init of a ForOfStatement, got ${declarations.length}`\n+ );\n+ const id = declarations[0].get(\"id\");\n+ const nextIterableOf = lowerValueToTemporary(builder, {\n+ kind: \"NextIterableOf\",\n+ loc: leftLoc,\n+ value,\n+ });\n+ const assign = lowerAssignment(\n+ builder,\n+ leftLoc,\n+ InstructionKind.Let,\n+ id,\n+ nextIterableOf\n+ );\n+ test = lowerValueToTemporary(builder, assign);\n+ } else {\n+ builder.errors.push({\n+ reason: `(BuildHIR::lowerStatement) Handle ${left.type} inits in ForOfStatement`,\n+ severity: ErrorSeverity.Todo,\n+ nodePath: left,\n+ });\n+ return;\n+ }\n+ builder.terminateWithContinuation(\n+ {\n+ id: makeInstructionId(0),\n+ kind: \"branch\",\n+ test,\n+ consequent: loopBlock,\n+ alternate: continuationBlock.id,\n+ },\n+ continuationBlock\n+ );\n+ return;\n+ }\n case \"ForInStatement\":\n case \"ClassDeclaration\":\n case \"DebuggerStatement\":\ndiff --git a\/compiler\/forget\/src\/HIR\/HIR.ts b\/compiler\/forget\/src\/HIR\/HIR.ts\nindex ea2d29f657..5e70158bac 100644\n--- a\/compiler\/forget\/src\/HIR\/HIR.ts\n+++ b\/compiler\/forget\/src\/HIR\/HIR.ts\n@@ -134,6 +134,7 @@ export type ReactiveTerminal =\n | ReactiveDoWhileTerminal\n | ReactiveWhileTerminal\n | ReactiveForTerminal\n+ | ReactiveForOfTerminal\n | ReactiveIfTerminal;\n \n export type ReactiveBreakTerminal = {\n@@ -187,6 +188,12 @@ export type ReactiveForTerminal = {\n loop: ReactiveBlock;\n id: InstructionId;\n };\n+export type ReactiveForOfTerminal = {\n+ kind: \"for-of\";\n+ init: ReactiveValue;\n+ loop: ReactiveBlock;\n+ id: InstructionId;\n+};\n export type ReactiveIfTerminal = {\n kind: \"if\";\n test: Place;\n@@ -257,6 +264,7 @@ export type Terminal =\n | BranchTerminal\n | SwitchTerminal\n | ForTerminal\n+ | ForOfTerminal\n | DoWhileTerminal\n | WhileTerminal\n | LogicalTerminal\n@@ -345,6 +353,15 @@ export type ForTerminal = {\n id: InstructionId;\n };\n \n+export type ForOfTerminal = {\n+ kind: \"for-of\";\n+ loc: SourceLocation;\n+ init: BlockId;\n+ loop: BlockId;\n+ fallthrough: BlockId;\n+ id: InstructionId;\n+};\n+\n export type LogicalTerminal = {\n kind: \"logical\";\n operator: t.LogicalExpression[\"operator\"];\n@@ -638,6 +655,11 @@ export type InstructionValue =\n value: Place;\n loc: SourceLocation;\n }\n+ | {\n+ kind: \"NextIterableOf\";\n+ value: Place; \/\/ the collection\n+ loc: SourceLocation;\n+ }\n \/**\n * Catch-all for statements such as type imports, nested class declarations, etc\n * which are not directly represented, but included for completeness and to allow\ndiff --git a\/compiler\/forget\/src\/HIR\/HIRBuilder.ts b\/compiler\/forget\/src\/HIR\/HIRBuilder.ts\nindex bd39ffee1b..3fc17f7c08 100644\n--- a\/compiler\/forget\/src\/HIR\/HIRBuilder.ts\n+++ b\/compiler\/forget\/src\/HIR\/HIRBuilder.ts\n@@ -661,6 +661,10 @@ export function reversePostorderBlocks(func: HIR): void {\n visit(terminal.init);\n break;\n }\n+ case \"for-of\": {\n+ visit(terminal.init);\n+ break;\n+ }\n case \"unsupported\": {\n break;\n }\ndiff --git a\/compiler\/forget\/src\/HIR\/PrintHIR.ts b\/compiler\/forget\/src\/HIR\/PrintHIR.ts\nindex 32f658a93d..9593125d77 100644\n--- a\/compiler\/forget\/src\/HIR\/PrintHIR.ts\n+++ b\/compiler\/forget\/src\/HIR\/PrintHIR.ts\n@@ -91,7 +91,8 @@ export function printMixedHIR(\n case \"for\":\n case \"unsupported\":\n case \"goto\":\n- case \"do-while\": {\n+ case \"do-while\":\n+ case \"for-of\": {\n const terminal = printTerminal(value);\n if (Array.isArray(terminal)) {\n return terminal.join(\"; \");\n@@ -208,6 +209,10 @@ export function printTerminal(terminal: Terminal): Array | string {\n value = `[${terminal.id}] For init=bb${terminal.init} test=bb${terminal.test} loop=bb${terminal.loop} update=bb${terminal.update} fallthrough=bb${terminal.fallthrough}`;\n break;\n }\n+ case \"for-of\": {\n+ value = `[${terminal.id}] ForOf init=bb${terminal.init} loop=bb${terminal.loop} fallthrough=bb${terminal.fallthrough}`;\n+ break;\n+ }\n case \"unsupported\": {\n value = `Unsupported`;\n break;\n@@ -452,6 +457,10 @@ export function printInstructionValue(instrValue: ReactiveValue): string {\n value = `Await ${printPlace(instrValue.value)}`;\n break;\n }\n+ case \"NextIterableOf\": {\n+ value = `NextIterableOf ${printPlace(instrValue.value)}`;\n+ break;\n+ }\n default: {\n assertExhaustive(\n instrValue,\ndiff --git a\/compiler\/forget\/src\/HIR\/visitors.ts b\/compiler\/forget\/src\/HIR\/visitors.ts\nindex 328a995466..9256a6c4bc 100644\n--- a\/compiler\/forget\/src\/HIR\/visitors.ts\n+++ b\/compiler\/forget\/src\/HIR\/visitors.ts\n@@ -174,6 +174,10 @@ export function* eachInstructionValueOperand(\n yield instrValue.value;\n break;\n }\n+ case \"NextIterableOf\": {\n+ yield instrValue.value;\n+ break;\n+ }\n case \"RegExpLiteral\":\n case \"LoadGlobal\":\n case \"UnsupportedNode\":\n@@ -431,6 +435,10 @@ export function mapInstructionOperands(\n instrValue.value = fn(instrValue.value);\n break;\n }\n+ case \"NextIterableOf\": {\n+ instrValue.value = fn(instrValue.value);\n+ break;\n+ }\n case \"RegExpLiteral\":\n case \"LoadGlobal\":\n case \"UnsupportedNode\":\n@@ -638,6 +646,19 @@ export function mapTerminalSuccessors(\n id: makeInstructionId(0),\n };\n }\n+ case \"for-of\": {\n+ const init = fn(terminal.init);\n+ const loop = fn(terminal.loop);\n+ const fallthrough = fn(terminal.fallthrough);\n+ return {\n+ kind: \"for-of\",\n+ loc: terminal.loc,\n+ init,\n+ loop,\n+ fallthrough,\n+ id: makeInstructionId(0),\n+ };\n+ }\n case \"unsupported\": {\n return terminal;\n }\n@@ -701,6 +722,10 @@ export function* eachTerminalSuccessor(terminal: Terminal): Iterable {\n yield terminal.init;\n break;\n }\n+ case \"for-of\": {\n+ yield terminal.init;\n+ break;\n+ }\n case \"unsupported\":\n break;\n default: {\n@@ -748,6 +773,7 @@ export function mapTerminalOperands(\n case \"do-while\":\n case \"while\":\n case \"for\":\n+ case \"for-of\":\n case \"goto\":\n case \"unsupported\": {\n \/\/ no-op\n@@ -795,6 +821,7 @@ export function* eachTerminalOperand(terminal: Terminal): Iterable {\n case \"do-while\":\n case \"while\":\n case \"for\":\n+ case \"for-of\":\n case \"goto\":\n case \"unsupported\": {\n \/\/ no-op\ndiff --git a\/compiler\/forget\/src\/Inference\/InferReferenceEffects.ts b\/compiler\/forget\/src\/Inference\/InferReferenceEffects.ts\nindex ee1407dee3..2f5892a1cd 100644\n--- a\/compiler\/forget\/src\/Inference\/InferReferenceEffects.ts\n+++ b\/compiler\/forget\/src\/Inference\/InferReferenceEffects.ts\n@@ -874,6 +874,12 @@ function inferBlock(\n }\n continue;\n }\n+ case \"NextIterableOf\": {\n+ effectKind = Effect.Capture;\n+ lvalueEffect = Effect.Store;\n+ valueKind = ValueKind.Mutable;\n+ break;\n+ }\n default: {\n assertExhaustive(instrValue, \"Unexpected instruction kind\");\n }\ndiff --git a\/compiler\/forget\/src\/Optimization\/DeadCodeElimination.ts b\/compiler\/forget\/src\/Optimization\/DeadCodeElimination.ts\nindex 877a2340a4..d30188ea60 100644\n--- a\/compiler\/forget\/src\/Optimization\/DeadCodeElimination.ts\n+++ b\/compiler\/forget\/src\/Optimization\/DeadCodeElimination.ts\n@@ -208,6 +208,11 @@ function pruneableValue(value: InstructionValue, state: State): boolean {\n \/\/ Potentially safe to prune, since they should just be creating new values\n return false;\n }\n+ case \"NextIterableOf\": {\n+ \/\/ Technically a NextIterableOf will never be unused because it's always used later by\n+ \/\/ another StoreLocal or Destructure instruction, but conceptually we can't prune\n+ return false;\n+ }\n case \"RegExpLiteral\":\n case \"LoadGlobal\":\n case \"ArrayExpression\":\ndiff --git a\/compiler\/forget\/src\/ReactiveScopes\/BuildReactiveFunction.ts b\/compiler\/forget\/src\/ReactiveScopes\/BuildReactiveFunction.ts\nindex 65c063b3df..f35d065085 100644\n--- a\/compiler\/forget\/src\/ReactiveScopes\/BuildReactiveFunction.ts\n+++ b\/compiler\/forget\/src\/ReactiveScopes\/BuildReactiveFunction.ts\n@@ -417,6 +417,79 @@ class Driver {\n }\n break;\n }\n+ case \"for-of\": {\n+ const loopId =\n+ !this.cx.isScheduled(terminal.loop) &&\n+ terminal.loop !== terminal.fallthrough\n+ ? terminal.loop\n+ : null;\n+\n+ const fallthroughId =\n+ terminal.fallthrough !== null &&\n+ !this.cx.isScheduled(terminal.fallthrough)\n+ ? terminal.fallthrough\n+ : null;\n+\n+ const scheduleId = this.cx.scheduleLoop(\n+ terminal.fallthrough,\n+ terminal.init,\n+ terminal.loop\n+ );\n+ scheduleIds.push(scheduleId);\n+\n+ const init = this.visitValueBlock(terminal.init, terminal.loc);\n+ const initBlock = this.cx.ir.blocks.get(init.block)!;\n+ let initValue = init.value;\n+ if (initValue.kind === \"SequenceExpression\") {\n+ const last = initBlock.instructions.at(-1)!;\n+ initValue.instructions.push(last);\n+ initValue.value = {\n+ kind: \"Primitive\",\n+ value: undefined,\n+ loc: terminal.loc,\n+ };\n+ } else {\n+ initValue = {\n+ kind: \"SequenceExpression\",\n+ instructions: [initBlock.instructions.at(-1)!],\n+ id: terminal.id,\n+ loc: terminal.loc,\n+ value: {\n+ kind: \"Primitive\",\n+ value: undefined,\n+ loc: terminal.loc,\n+ },\n+ };\n+ }\n+\n+ let loopBody: ReactiveBlock;\n+ if (loopId) {\n+ loopBody = this.traverseBlock(this.cx.ir.blocks.get(loopId)!);\n+ } else {\n+ const break_ = this.visitBreak(terminal.loop, null);\n+ invariant(\n+ break_ !== null,\n+ \"If loop body is already scheduled it must be a break\"\n+ );\n+ loopBody = [break_];\n+ }\n+\n+ this.cx.unscheduleAll(scheduleIds);\n+ blockValue.push({\n+ kind: \"terminal\",\n+ terminal: {\n+ kind: \"for-of\",\n+ init: initValue,\n+ loop: loopBody,\n+ id: terminal.id,\n+ },\n+ label: fallthroughId,\n+ });\n+ if (fallthroughId !== null) {\n+ this.visitBlock(this.cx.ir.blocks.get(fallthroughId)!, blockValue);\n+ }\n+ break;\n+ }\n case \"branch\": {\n let consequent: ReactiveBlock | null = null;\n if (this.cx.isScheduled(terminal.consequent)) {\ndiff --git a\/compiler\/forget\/src\/ReactiveScopes\/CodegenReactiveFunction.ts b\/compiler\/forget\/src\/ReactiveScopes\/CodegenReactiveFunction.ts\nindex a2ac1c98ca..73beeb5447 100644\n--- a\/compiler\/forget\/src\/ReactiveScopes\/CodegenReactiveFunction.ts\n+++ b\/compiler\/forget\/src\/ReactiveScopes\/CodegenReactiveFunction.ts\n@@ -310,6 +310,66 @@ function codegenTerminal(\n codegenBlock(cx, terminal.loop)\n );\n }\n+ case \"for-of\": {\n+ if (terminal.init.kind !== \"SequenceExpression\") {\n+ CompilerError.invariant(\n+ `Expected a sequence expression init for ForOf, got: ${terminal.init.kind}`,\n+ terminal.init.loc\n+ );\n+ }\n+ if (terminal.init.instructions.length !== 2) {\n+ CompilerError.todo(\n+ \"Support non-trivial ForOf inits\",\n+ terminal.init.loc\n+ );\n+ }\n+ const iterableCollection = terminal.init.instructions[0];\n+ const iterableItem = terminal.init.instructions[1];\n+ let lval: t.LVal;\n+ switch (iterableItem.value.kind) {\n+ case \"StoreLocal\": {\n+ lval = codegenLValue(iterableItem.value.lvalue.place);\n+ break;\n+ }\n+ case \"Destructure\": {\n+ lval = codegenLValue(iterableItem.value.lvalue.pattern);\n+ break;\n+ }\n+ default:\n+ CompilerError.invariant(\n+ `Expected a StoreLocal or Destructure to be assigned to the collection, got: ${iterableItem.value.kind}`,\n+ iterableItem.value.loc\n+ );\n+ }\n+ let varDeclKind: \"const\" | \"let\";\n+ switch (iterableItem.value.lvalue.kind) {\n+ case InstructionKind.Const:\n+ varDeclKind = \"const\" as const;\n+ break;\n+ case InstructionKind.Let:\n+ varDeclKind = \"let\" as const;\n+ break;\n+ case InstructionKind.Reassign:\n+ CompilerError.invariant(\n+ \"Destructure should never be Reassign as it would be an Object\/ArrayPattern\",\n+ iterableItem.loc\n+ );\n+ default:\n+ assertExhaustive(\n+ iterableItem.value.lvalue.kind,\n+ `Unhandled lvalue kind: ${iterableItem.value.lvalue.kind}`\n+ );\n+ }\n+ return t.forOfStatement(\n+ \/\/ Special handling here since we only want the VariableDeclarators without any inits\n+ \/\/ This needs to be updated when we handle non-trivial ForOf inits\n+ createVariableDeclaration(iterableItem.value.loc, varDeclKind, [\n+ t.variableDeclarator(lval, null),\n+ ]),\n+ codegenInstructionValue(cx, iterableCollection.value),\n+ codegenBlock(cx, terminal.loop)\n+ );\n+ }\n case \"if\": {\n return t.ifStatement(\n codegenPlace(cx, terminal.test),\n@@ -923,6 +983,10 @@ function codegenInstructionValue(\n value = t.awaitExpression(codegenPlace(cx, instrValue.value));\n break;\n }\n+ case \"NextIterableOf\": {\n+ value = codegenPlace(cx, instrValue.value);\n+ break;\n+ }\n case \"DeclareLocal\":\n case \"Destructure\":\n case \"StoreLocal\": {\ndiff --git a\/compiler\/forget\/src\/ReactiveScopes\/FlattenReactiveLoops.ts b\/compiler\/forget\/src\/ReactiveScopes\/FlattenReactiveLoops.ts\nindex a29e58a4ce..1994466a25 100644\n--- a\/compiler\/forget\/src\/ReactiveScopes\/FlattenReactiveLoops.ts\n+++ b\/compiler\/forget\/src\/ReactiveScopes\/FlattenReactiveLoops.ts\n@@ -48,7 +48,8 @@ class Transform extends ReactiveFunctionTransform {\n \/\/ Loop terminals flatten nested scopes\n case \"do-while\":\n case \"while\":\n- case \"for\": {\n+ case \"for\":\n+ case \"for-of\": {\n this.traverseTerminal(stmt, true);\n break;\n }\ndiff --git a\/compiler\/forget\/src\/ReactiveScopes\/InferReactiveScopeVariables.ts b\/compiler\/forget\/src\/ReactiveScopes\/InferReactiveScopeVariables.ts\nindex 8f519f6e04..e67d1eb57c 100644\n--- a\/compiler\/forget\/src\/ReactiveScopes\/InferReactiveScopeVariables.ts\n+++ b\/compiler\/forget\/src\/ReactiveScopes\/InferReactiveScopeVariables.ts\n@@ -233,7 +233,8 @@ function mayAllocate(value: InstructionValue): boolean {\n case \"JSXText\":\n case \"UnaryExpression\":\n case \"TemplateLiteral\":\n- case \"Primitive\": {\n+ case \"Primitive\":\n+ case \"NextIterableOf\": {\n return false;\n }\n case \"RegExpLiteral\":\ndiff --git a\/compiler\/forget\/src\/ReactiveScopes\/PrintReactiveFunction.ts b\/compiler\/forget\/src\/ReactiveScopes\/PrintReactiveFunction.ts\nindex 206b8b076e..ac8365c535 100644\n--- a\/compiler\/forget\/src\/ReactiveScopes\/PrintReactiveFunction.ts\n+++ b\/compiler\/forget\/src\/ReactiveScopes\/PrintReactiveFunction.ts\n@@ -234,6 +234,14 @@ function printTerminal(writer: Writer, terminal: ReactiveTerminal): void {\n writer.writeLine(\"}\");\n break;\n }\n+ case \"for-of\": {\n+ writer.writeLine(`[${terminal.id}] for-of (`);\n+ printReactiveValue(writer, terminal.init);\n+ writer.writeLine(\") {\");\n+ printReactiveInstructions(writer, terminal.loop);\n+ writer.writeLine(\"}\");\n+ break;\n+ }\n case \"throw\": {\n writer.writeLine(`[${terminal.id}] throw ${printPlace(terminal.value)}`);\n break;\ndiff --git a\/compiler\/forget\/src\/ReactiveScopes\/PropagateScopeDependencies.ts b\/compiler\/forget\/src\/ReactiveScopes\/PropagateScopeDependencies.ts\nindex 9f62547056..9adf594cf2 100644\n--- a\/compiler\/forget\/src\/ReactiveScopes\/PropagateScopeDependencies.ts\n+++ b\/compiler\/forget\/src\/ReactiveScopes\/PropagateScopeDependencies.ts\n@@ -379,6 +379,13 @@ function visit(context: Context, block: ReactiveBlock): void {\n });\n break;\n }\n+ case \"for-of\": {\n+ visitReactiveValue(context, terminal.id, terminal.init);\n+ context.enterConditional(() => {\n+ visit(context, terminal.loop);\n+ });\n+ break;\n+ }\n case \"do-while\": {\n visit(context, terminal.loop);\n context.enterConditional(() => {\ndiff --git a\/compiler\/forget\/src\/ReactiveScopes\/PruneNonEscapingScopes.ts b\/compiler\/forget\/src\/ReactiveScopes\/PruneNonEscapingScopes.ts\nindex ec2ce6dbce..69bb34cb5d 100644\n--- a\/compiler\/forget\/src\/ReactiveScopes\/PruneNonEscapingScopes.ts\n+++ b\/compiler\/forget\/src\/ReactiveScopes\/PruneNonEscapingScopes.ts\n@@ -425,7 +425,8 @@ function computeMemoizationInputs(\n };\n }\n case \"Await\":\n- case \"TypeCastExpression\": {\n+ case \"TypeCastExpression\":\n+ case \"NextIterableOf\": {\n return {\n \/\/ Indirection for the inner value, memoized if the value is\n lvalues:\ndiff --git a\/compiler\/forget\/src\/ReactiveScopes\/visitors.ts b\/compiler\/forget\/src\/ReactiveScopes\/visitors.ts\nindex a7687cf266..7b0464cb5b 100644\n--- a\/compiler\/forget\/src\/ReactiveScopes\/visitors.ts\n+++ b\/compiler\/forget\/src\/ReactiveScopes\/visitors.ts\n@@ -112,6 +112,11 @@ export class ReactiveFunctionVisitor {\n this.visitBlock(terminal.loop, state);\n break;\n }\n+ case \"for-of\": {\n+ this.visitValue(terminal.id, terminal.init, state);\n+ this.visitBlock(terminal.loop, state);\n+ break;\n+ }\n case \"do-while\": {\n this.visitBlock(terminal.loop, state);\n this.visitValue(terminal.id, terminal.test, state);\n@@ -324,6 +329,10 @@ export function mapTerminalBlocks(\n terminal.loop = fn(terminal.loop);\n break;\n }\n+ case \"for-of\": {\n+ terminal.loop = fn(terminal.loop);\n+ break;\n+ }\n case \"do-while\":\n case \"while\": {\n terminal.loop = fn(terminal.loop);\ndiff --git a\/compiler\/forget\/src\/SSA\/LeaveSSA.ts b\/compiler\/forget\/src\/SSA\/LeaveSSA.ts\nindex 26c3b1af10..9a5d38ef8c 100644\n--- a\/compiler\/forget\/src\/SSA\/LeaveSSA.ts\n+++ b\/compiler\/forget\/src\/SSA\/LeaveSSA.ts\n@@ -190,7 +190,7 @@ export function leaveSSA(fn: HIRFunction): void {\n originalLVal === undefined ||\n originalLVal.lvalue === value.lvalue\n ) {\n- if (originalLVal === undefined && block.kind !== \"block\") {\n+ if (originalLVal === undefined && block.kind === \"value\") {\n CompilerError.invariant(\n `TODO: Handle reassignment in a value block where the original declaration was removed by dead code elimination (DCE)`,\n place.loc\n@@ -294,7 +294,8 @@ export function leaveSSA(fn: HIRFunction): void {\n (terminal.kind === \"if\" ||\n terminal.kind === \"switch\" ||\n terminal.kind === \"while\" ||\n- terminal.kind === \"for\") &&\n+ terminal.kind === \"for\" ||\n+ terminal.kind === \"for-of\") &&\n terminal.fallthrough !== null\n ) {\n const fallthrough = fn.body.blocks.get(terminal.fallthrough)!;\n@@ -307,7 +308,7 @@ export function leaveSSA(fn: HIRFunction): void {\n const loop = fn.body.blocks.get(terminal.loop)!;\n pushPhis(loop);\n }\n- if (terminal.kind === \"for\") {\n+ if (terminal.kind === \"for\" || terminal.kind === \"for-of\") {\n const init = fn.body.blocks.get(terminal.init)!;\n pushPhis(init);\n \n@@ -333,8 +334,10 @@ export function leaveSSA(fn: HIRFunction): void {\n }\n }\n \n- const update = fn.body.blocks.get(terminal.update)!;\n- pushPhis(update);\n+ if (terminal.kind === \"for\") {\n+ const update = fn.body.blocks.get(terminal.update)!;\n+ pushPhis(update);\n+ }\n }\n if (\n terminal.kind === \"logical\" ||\ndiff --git a\/compiler\/forget\/src\/TypeInference\/InferTypes.ts b\/compiler\/forget\/src\/TypeInference\/InferTypes.ts\nindex 8fafb2c60a..6ed242ddc1 100644\n--- a\/compiler\/forget\/src\/TypeInference\/InferTypes.ts\n+++ b\/compiler\/forget\/src\/TypeInference\/InferTypes.ts\n@@ -202,6 +202,7 @@ function* generateInstructionTypes(\n case \"TaggedTemplateExpression\":\n case \"TemplateLiteral\":\n case \"Await\":\n+ case \"NextIterableOf\":\n case \"UnsupportedNode\":\n break;\n default:\ndiff --git a\/compiler\/forget\/src\/Utils\/VisualizeHIRMermaid.ts b\/compiler\/forget\/src\/Utils\/VisualizeHIRMermaid.ts\nindex 19b0cfcf59..fe74d151ce 100644\n--- a\/compiler\/forget\/src\/Utils\/VisualizeHIRMermaid.ts\n+++ b\/compiler\/forget\/src\/Utils\/VisualizeHIRMermaid.ts\n@@ -121,6 +121,9 @@ function printTerminalLabel(terminal: Terminal): string {\n case \"for\":\n buffer.push(\"For\");\n break;\n+ case \"for-of\":\n+ buffer.push(\"ForOf\");\n+ break;\n case \"unsupported\": {\n break;\n }\n@@ -207,6 +210,11 @@ function printTerminalArrows(blockId: BlockId, terminal: Terminal): string {\n buffer.push(printJumpArrow(blockId, terminal.fallthrough, \"fallthrough\"));\n break;\n }\n+ case \"for-of\": {\n+ buffer.push(printJumpArrow(blockId, terminal.init, \"init\"));\n+ buffer.push(printJumpArrow(blockId, terminal.loop, \"loop\"));\n+ break;\n+ }\n case \"throw\":\n case \"return\":\n case \"unsupported\": {\ndiff --git a\/compiler\/forget\/src\/__tests__\/fixtures\/compiler\/error.ssa-for-of.expect.md b\/compiler\/forget\/src\/__tests__\/fixtures\/compiler\/error.ssa-for-of.expect.md\ndeleted file mode 100644\nindex 51ad74b35b..0000000000\n--- a\/compiler\/forget\/src\/__tests__\/fixtures\/compiler\/error.ssa-for-of.expect.md\n+++ \/dev\/null\n@@ -1,32 +0,0 @@\n-\n-## Input\n-\n-```javascript\n-function foo(cond) {\n- let items = [];\n- for (const item of items) {\n- let y = 0;\n- if (cond) {\n- y = 1;\n- }\n- }\n- return items;\n-}\n-\n-```\n-\n-\n-## Error\n-\n-```\n-[ReactForget] TodoError: (BuildHIR::lowerStatement) Handle ForOfStatement statements\n- 1 | function foo(cond) {\n- 2 | let items = [];\n-> 3 | for (const item of items) {\n- | ^\n- 4 | let y = 0;\n- 5 | if (cond) {\n- 6 | y = 1;\n-```\n- \n- \n\\ No newline at end of file\ndiff --git a\/compiler\/forget\/src\/__tests__\/fixtures\/compiler\/error.todo-kitchensink.expect.md b\/compiler\/forget\/src\/__tests__\/fixtures\/compiler\/error.todo-kitchensink.expect.md\nindex c3afa3e307..76492789a5 100644\n--- a\/compiler\/forget\/src\/__tests__\/fixtures\/compiler\/error.todo-kitchensink.expect.md\n+++ b\/compiler\/forget\/src\/__tests__\/fixtures\/compiler\/error.todo-kitchensink.expect.md\n@@ -37,7 +37,11 @@ function foo([a, b], { c, d, e = \"e\" }, f = \"f\", ...args) {\n \n graphql`\\\\t\\n`;\n \n- for (const c of [1, 2]) {\n+ for (c of [1, 2]) {\n+ }\n+ for ([v] of [[1], [2]]) {\n+ }\n+ for ({ v } of [{ v: 1 }, { v: 2 }]) {\n }\n \n for (let x in { a: 1 }) {\n@@ -191,107 +195,125 @@ let moduleLocal = false;\n > 34 | graphql`\\\\t\\n`;\n | ^^^^^^^^^^^^^^\n 35 |\n- 36 | for (const c of [1, 2]) {\n+ 36 | for (c of [1, 2]) {\n 37 | }\n \n-[ReactForget] TodoError: (BuildHIR::lowerStatement) Handle ForOfStatement statements\n+[ReactForget] TodoError: (BuildHIR::lowerStatement) Handle Identifier inits in ForOfStatement\n 34 | graphql`\\\\t\\n`;\n 35 |\n-> 36 | for (const c of [1, 2]) {\n- | ^\n+> 36 | for (c of [1, 2]) {\n+ | ^\n 37 | }\n- 38 |\n- 39 | for (let x in { a: 1 }) {\n+ 38 | for ([v] of [[1], [2]]) {\n+ 39 | }\n \n-[ReactForget] TodoError: (BuildHIR::lowerStatement) Handle ForInStatement statements\n+[ReactForget] TodoError: (BuildHIR::lowerStatement) Handle ArrayPattern inits in ForOfStatement\n+ 36 | for (c of [1, 2]) {\n 37 | }\n- 38 |\n-> 39 | for (let x in { a: 1 }) {\n+> 38 | for ([v] of [[1], [2]]) {\n+ | ^^^\n+ 39 | }\n+ 40 | for ({ v } of [{ v: 1 }, { v: 2 }]) {\n+ 41 | }\n+\n+[ReactForget] TodoError: (BuildHIR::lowerStatement) Handle ObjectPattern inits in ForOfStatement\n+ 38 | for ([v] of [[1], [2]]) {\n+ 39 | }\n+> 40 | for ({ v } of [{ v: 1 }, { v: 2 }]) {\n+ | ^^^^^\n+ 41 | }\n+ 42 |\n+ 43 | for (let x in { a: 1 }) {\n+\n+[ReactForget] TodoError: (BuildHIR::lowerStatement) Handle ForInStatement statements\n+ 41 | }\n+ 42 |\n+> 43 | for (let x in { a: 1 }) {\n | ^\n- 40 | }\n- 41 |\n- 42 | let updateIdentifier = 0;\n+ 44 | }\n+ 45 |\n+ 46 | let updateIdentifier = 0;\n \n [ReactForget] TodoError: (BuildHIR::lowerExpression) Handle prefix UpdateExpression\n- 41 |\n- 42 | let updateIdentifier = 0;\n-> 43 | --updateIdentifier;\n+ 45 |\n+ 46 | let updateIdentifier = 0;\n+> 47 | --updateIdentifier;\n | ^^^^^^^^^^^^^^^^^^\n- 44 | ++updateIdentifier;\n- 45 | updateIdentifier.y++;\n- 46 | updateIdentifier.y--;\n+ 48 | ++updateIdentifier;\n+ 49 | updateIdentifier.y++;\n+ 50 | updateIdentifier.y--;\n \n [ReactForget] TodoError: (BuildHIR::lowerExpression) Handle prefix UpdateExpression\n- 42 | let updateIdentifier = 0;\n- 43 | --updateIdentifier;\n-> 44 | ++updateIdentifier;\n+ 46 | let updateIdentifier = 0;\n+ 47 | --updateIdentifier;\n+> 48 | ++updateIdentifier;\n | ^^^^^^^^^^^^^^^^^^\n- 45 | updateIdentifier.y++;\n- 46 | updateIdentifier.y--;\n- 47 |\n+ 49 | updateIdentifier.y++;\n+ 50 | updateIdentifier.y--;\n+ 51 |\n \n [ReactForget] TodoError: (BuildHIR::lowerExpression) Handle UpdateExpression with MemberExpression argument\n- 43 | --updateIdentifier;\n- 44 | ++updateIdentifier;\n-> 45 | updateIdentifier.y++;\n+ 47 | --updateIdentifier;\n+ 48 | ++updateIdentifier;\n+> 49 | updateIdentifier.y++;\n | ^^^^^^^^^^^^^^^^^^^^\n- 46 | updateIdentifier.y--;\n- 47 |\n- 48 | switch (i) {\n+ 50 | updateIdentifier.y--;\n+ 51 |\n+ 52 | switch (i) {\n \n [ReactForget] TodoError: (BuildHIR::lowerExpression) Handle UpdateExpression with MemberExpression argument\n- 44 | ++updateIdentifier;\n- 45 | updateIdentifier.y++;\n-> 46 | updateIdentifier.y--;\n+ 48 | ++updateIdentifier;\n+ 49 | updateIdentifier.y++;\n+> 50 | updateIdentifier.y--;\n | ^^^^^^^^^^^^^^^^^^^^\n- 47 |\n- 48 | switch (i) {\n- 49 | case 1 + 1: {\n+ 51 |\n+ 52 | switch (i) {\n+ 53 | case 1 + 1: {\n \n [ReactForget] TodoError: (BuildHIR::node.lowerReorderableExpression) Expression type 'MemberExpression' cannot be safely reordered\n- 51 | case foo(): {\n- 52 | }\n-> 53 | case x.y: {\n- | ^^^\n- 54 | }\n- 55 | default: {\n+ 55 | case foo(): {\n 56 | }\n+> 57 | case x.y: {\n+ | ^^^\n+ 58 | }\n+ 59 | default: {\n+ 60 | }\n \n [ReactForget] TodoError: (BuildHIR::node.lowerReorderableExpression) Expression type 'CallExpression' cannot be safely reordered\n- 49 | case 1 + 1: {\n- 50 | }\n-> 51 | case foo(): {\n- | ^^^^^\n- 52 | }\n- 53 | case x.y: {\n+ 53 | case 1 + 1: {\n 54 | }\n+> 55 | case foo(): {\n+ | ^^^^^\n+ 56 | }\n+ 57 | case x.y: {\n+ 58 | }\n \n [ReactForget] TodoError: (BuildHIR::node.lowerReorderableExpression) Expression type 'BinaryExpression' cannot be safely reordered\n- 47 |\n- 48 | switch (i) {\n-> 49 | case 1 + 1: {\n+ 51 |\n+ 52 | switch (i) {\n+> 53 | case 1 + 1: {\n | ^^^^^\n- 50 | }\n- 51 | case foo(): {\n- 52 | }\n+ 54 | }\n+ 55 | case foo(): {\n+ 56 | }\n \n [ReactForget] InvalidInputError: (BuildHIR::lowerAssignment) Assigning to an identifier defined outside the function scope is not supported.\n- 58 |\n- 59 | \/\/ Cannot assign to globals\n-> 60 | someUnknownGlobal = true;\n- | ^^^^^^^^^^^^^^^^^\n- 61 | moduleLocal = true;\n 62 |\n- 63 | function component(a) {\n+ 63 | \/\/ Cannot assign to globals\n+> 64 | someUnknownGlobal = true;\n+ | ^^^^^^^^^^^^^^^^^\n+ 65 | moduleLocal = true;\n+ 66 |\n+ 67 | function component(a) {\n \n [ReactForget] InvalidInputError: (BuildHIR::lowerAssignment) Assigning to an identifier defined outside the function scope is not supported.\n- 59 | \/\/ Cannot assign to globals\n- 60 | someUnknownGlobal = true;\n-> 61 | moduleLocal = true;\n+ 63 | \/\/ Cannot assign to globals\n+ 64 | someUnknownGlobal = true;\n+> 65 | moduleLocal = true;\n | ^^^^^^^^^^^\n- 62 |\n- 63 | function component(a) {\n- 64 | \/\/ Add support for function declarations once we support `var` hoisting.\n+ 66 |\n+ 67 | function component(a) {\n+ 68 | \/\/ Add support for function declarations once we support `var` hoisting.\n ```\n \n \n\\ No newline at end of file\ndiff --git a\/compiler\/forget\/src\/__tests__\/fixtures\/compiler\/error.todo-kitchensink.js b\/compiler\/forget\/src\/__tests__\/fixtures\/compiler\/error.todo-kitchensink.js\nindex ed442e4737..32250ac273 100644\n--- a\/compiler\/forget\/src\/__tests__\/fixtures\/compiler\/error.todo-kitchensink.js\n+++ b\/compiler\/forget\/src\/__tests__\/fixtures\/compiler\/error.todo-kitchensink.js\n@@ -33,7 +33,11 @@ function foo([a, b], { c, d, e = \"e\" }, f = \"f\", ...args) {\n \n graphql`\\\\t\\n`;\n \n- for (const c of [1, 2]) {\n+ for (c of [1, 2]) {\n+ }\n+ for ([v] of [[1], [2]]) {\n+ }\n+ for ({ v } of [{ v: 1 }, { v: 2 }]) {\n }\n \n for (let x in { a: 1 }) {\ndiff --git a\/compiler\/forget\/src\/__tests__\/fixtures\/compiler\/for-of-break.expect.md b\/compiler\/forget\/src\/__tests__\/fixtures\/compiler\/for-of-break.expect.md\nnew file mode 100644\nindex 0000000000..c36b7d7f18\n--- \/dev\/null\n+++ b\/compiler\/forget\/src\/__tests__\/fixtures\/compiler\/for-of-break.expect.md\n@@ -0,0 +1,35 @@\n+\n+## Input\n+\n+```javascript\n+function Component() {\n+ const x = [];\n+ for (const item of [1, 2]) {\n+ break;\n+ }\n+ return x;\n+}\n+\n+```\n+\n+## Code\n+\n+```javascript\n+function Component() {\n+ const $ = React.unstable_useMemoCache(1);\n+ let t0;\n+ if ($[0] === Symbol.for(\"react.memo_cache_sentinel\")) {\n+ t0 = [];\n+ $[0] = t0;\n+ } else {\n+ t0 = $[0];\n+ }\n+ const x = t0;\n+ for (const item of [1, 2]) {\n+ break;\n+ }\n+ return x;\n+}\n+\n+```\n+ \n\\ No newline at end of file\ndiff --git a\/compiler\/forget\/src\/__tests__\/fixtures\/compiler\/for-of-break.js b\/compiler\/forget\/src\/__tests__\/fixtures\/compiler\/for-of-break.js\nnew file mode 100644\nindex 0000000000..1248bc8306\n--- \/dev\/null\n+++ b\/compiler\/forget\/src\/__tests__\/fixtures\/compiler\/for-of-break.js\n@@ -0,0 +1,7 @@\n+function Component() {\n+ const x = [];\n+ for (const item of [1, 2]) {\n+ break;\n+ }\n+ return x;\n+}\ndiff --git a\/compiler\/forget\/src\/__tests__\/fixtures\/compiler\/for-of-conditional-break.expect.md b\/compiler\/forget\/src\/__tests__\/fixtures\/compiler\/for-of-conditional-break.expect.md\nnew file mode 100644\nindex 0000000000..a015c656a0\n--- \/dev\/null\n+++ b\/compiler\/forget\/src\/__tests__\/fixtures\/compiler\/for-of-conditional-break.expect.md\n@@ -0,0 +1,48 @@\n+\n+## Input\n+\n+```javascript\n+function Component() {\n+ const x = [];\n+ for (const item of [1, 2]) {\n+ if (item === 1) {\n+ break;\n+ }\n+ x.push(item);\n+ }\n+ return x;\n+}\n+\n+```\n+\n+## Code\n+\n+```javascript\n+function Component() {\n+ const $ = React.unstable_useMemoCache(2);\n+ let x;\n+ if ($[0] === Symbol.for(\"react.memo_cache_sentinel\")) {\n+ x = [];\n+ let t0;\n+ if ($[1] === Symbol.for(\"react.memo_cache_sentinel\")) {\n+ t0 = [1, 2];\n+ $[1] = t0;\n+ } else {\n+ t0 = $[1];\n+ }\n+ for (const item of t0) {\n+ if (item === 1) {\n+ break;\n+ }\n+\n+ x.push(item);\n+ }\n+ $[0] = x;\n+ } else {\n+ x = $[0];\n+ }\n+ return x;\n+}\n+\n+```\n+ \n\\ No newline at end of file\ndiff --git a\/compiler\/forget\/src\/__tests__\/fixtures\/compiler\/for-of-conditional-break.js b\/compiler\/forget\/src\/__tests__\/fixtures\/compiler\/for-of-conditional-break.js\nnew file mode 100644\nindex 0000000000..23ebd337a8\n--- \/dev\/null\n+++ b\/compiler\/forget\/src\/__tests__\/fixtures\/compiler\/for-of-conditional-break.js\n@@ -0,0 +1,10 @@\n+function Component() {\n+ const x = [];\n+ for (const item of [1, 2]) {\n+ if (item === 1) {\n+ break;\n+ }\n+ x.push(item);\n+ }\n+ return x;\n+}\ndiff --git a\/compiler\/forget\/src\/__tests__\/fixtures\/compiler\/for-of-continue.expect.md b\/compiler\/forget\/src\/__tests__\/fixtures\/compiler\/for-of-continue.expect.md\nnew file mode 100644\nindex 0000000000..f89fa0eced\n--- \/dev\/null\n+++ b\/compiler\/forget\/src\/__tests__\/fixtures\/compiler\/for-of-continue.expect.md\n@@ -0,0 +1,50 @@\n+\n+## Input\n+\n+```javascript\n+function Component() {\n+ const x = [0, 1, 2, 3];\n+ const ret = [];\n+ for (const item of x) {\n+ if (item === 0) {\n+ continue;\n+ }\n+ ret.push(item \/ 2);\n+ }\n+ return ret;\n+}\n+\n+```\n+\n+## Code\n+\n+```javascript\n+function Component() {\n+ const $ = React.unstable_useMemoCache(2);\n+ let t0;\n+ if ($[0] === Symbol.for(\"react.memo_cache_sentinel\")) {\n+ t0 = [0, 1, 2, 3];\n+ $[0] = t0;\n+ } else {\n+ t0 = $[0];\n+ }\n+ const x = t0;\n+ let ret;\n+ if ($[1] === Symbol.for(\"react.memo_cache_sentinel\")) {\n+ ret = [];\n+ for (const item of x) {\n+ if (item === 0) {\n+ continue;\n+ }\n+\n+ ret.push(item \/ 2);\n+ }\n+ $[1] = ret;\n+ } else {\n+ ret = $[1];\n+ }\n+ return ret;\n+}\n+\n+```\n+ \n\\ No newline at end of file\ndiff --git a\/compiler\/forget\/src\/__tests__\/fixtures\/compiler\/for-of-continue.js b\/compiler\/forget\/src\/__tests__\/fixtures\/compiler\/for-of-continue.js\nnew file mode 100644\nindex 0000000000..4f5e878ba3\n--- \/dev\/null\n+++ b\/compiler\/forget\/src\/__tests__\/fixtures\/compiler\/for-of-continue.js\n@@ -0,0 +1,11 @@\n+function Component() {\n+ const x = [0, 1, 2, 3];\n+ const ret = [];\n+ for (const item of x) {\n+ if (item === 0) {\n+ continue;\n+ }\n+ ret.push(item \/ 2);\n+ }\n+ return ret;\n+}\ndiff --git a\/compiler\/forget\/src\/__tests__\/fixtures\/compiler\/for-of-destructure.expect.md b\/compiler\/forget\/src\/__tests__\/fixtures\/compiler\/for-of-destructure.expect.md\nnew file mode 100644\nindex 0000000000..d42886a290\n--- \/dev\/null\n+++ b\/compiler\/forget\/src\/__tests__\/fixtures\/compiler\/for-of-destructure.expect.md\n@@ -0,0 +1,36 @@\n+\n+## Input\n+\n+```javascript\n+function Component() {\n+ let x = [];\n+ let items = [{ v: 0 }, { v: 1 }, { v: 2 }];\n+ for (const { v } of items) {\n+ x.push(v * 2);\n+ }\n+ return x;\n+}\n+\n+```\n+\n+## Code\n+\n+```javascript\n+function Component() {\n+ const $ = React.unstable_useMemoCache(1);\n+ let x;\n+ if ($[0] === Symbol.for(\"react.memo_cache_sentinel\")) {\n+ x = [];\n+ const items = [{ v: 0 }, { v: 1 }, { v: 2 }];\n+ for (const { v } of items) {\n+ x.push(v * 2);\n+ }\n+ $[0] = x;\n+ } else {\n+ x = $[0];\n+ }\n+ return x;\n+}\n+\n+```\n+ \n\\ No newline at end of file\ndiff --git a\/compiler\/forget\/src\/__tests__\/fixtures\/compiler\/for-of-destructure.js b\/compiler\/forget\/src\/__tests__\/fixtures\/compiler\/for-of-destructure.js\nnew file mode 100644\nindex 0000000000..480bb662dd\n--- \/dev\/null\n+++ b\/compiler\/forget\/src\/__tests__\/fixtures\/compiler\/for-of-destructure.js\n@@ -0,0 +1,8 @@\n+function Component() {\n+ let x = [];\n+ let items = [{ v: 0 }, { v: 1 }, { v: 2 }];\n+ for (const { v } of items) {\n+ x.push(v * 2);\n+ }\n+ return x;\n+}\ndiff --git a\/compiler\/forget\/src\/__tests__\/fixtures\/compiler\/for-of-mutate.expect.md b\/compiler\/forget\/src\/__tests__\/fixtures\/compiler\/for-of-mutate.expect.md\nnew file mode 100644\nindex 0000000000..205a02af1e\n--- \/dev\/null\n+++ b\/compiler\/forget\/src\/__tests__\/fixtures\/compiler\/for-of-mutate.expect.md\n@@ -0,0 +1,43 @@\n+\n+## Input\n+\n+```javascript\n+function Component(props) {\n+ const collection = [makeObject()];\n+ const results = [];\n+ for (const item of collection) {\n+ results.push(

{mutate(item)}<\/div>);\n+ }\n+ return

{results}<\/div>;\n+}\n+\n+```\n+\n+## Code\n+\n+```javascript\n+function Component(props) {\n+ const $ = React.unstable_useMemoCache(2);\n+ let results;\n+ if ($[0] === Symbol.for(\"react.memo_cache_sentinel\")) {\n+ const collection = [makeObject()];\n+ results = [];\n+ for (const item of collection) {\n+ results.push(

{mutate(item)}<\/div>);\n+ }\n+ $[0] = results;\n+ } else {\n+ results = $[0];\n+ }\n+ let t0;\n+ if ($[1] === Symbol.for(\"react.memo_cache_sentinel\")) {\n+ t0 =

{results}<\/div>;\n+ $[1] = t0;\n+ } else {\n+ t0 = $[1];\n+ }\n+ return t0;\n+}\n+\n+```\n+ \n\\ No newline at end of file\ndiff --git a\/compiler\/forget\/src\/__tests__\/fixtures\/compiler\/for-of-mutate.js b\/compiler\/forget\/src\/__tests__\/fixtures\/compiler\/for-of-mutate.js\nnew file mode 100644\nindex 0000000000..ea7d16c938\n--- \/dev\/null\n+++ b\/compiler\/forget\/src\/__tests__\/fixtures\/compiler\/for-of-mutate.js\n@@ -0,0 +1,8 @@\n+function Component(props) {\n+ const collection = [makeObject()];\n+ const results = [];\n+ for (const item of collection) {\n+ results.push(

{mutate(item)}<\/div>);\n+ }\n+ return

{results}<\/div>;\n+}\ndiff --git a\/compiler\/forget\/src\/__tests__\/fixtures\/compiler\/for-of-simple.expect.md b\/compiler\/forget\/src\/__tests__\/fixtures\/compiler\/for-of-simple.expect.md\nnew file mode 100644\nindex 0000000000..2b200c3d71\n--- \/dev\/null\n+++ b\/compiler\/forget\/src\/__tests__\/fixtures\/compiler\/for-of-simple.expect.md\n@@ -0,0 +1,36 @@\n+\n+## Input\n+\n+```javascript\n+function Component() {\n+ let x = [];\n+ let items = [0, 1, 2];\n+ for (const ii of items) {\n+ x.push(ii * 2);\n+ }\n+ return x;\n+}\n+\n+```\n+\n+## Code\n+\n+```javascript\n+function Component() {\n+ const $ = React.unstable_useMemoCache(1);\n+ let x;\n+ if ($[0] === Symbol.for(\"react.memo_cache_sentinel\")) {\n+ x = [];\n+ const items = [0, 1, 2];\n+ for (const ii of items) {\n+ x.push(ii * 2);\n+ }\n+ $[0] = x;\n+ } else {\n+ x = $[0];\n+ }\n+ return x;\n+}\n+\n+```\n+ \n\\ No newline at end of file\ndiff --git a\/compiler\/forget\/src\/__tests__\/fixtures\/compiler\/for-of-simple.js b\/compiler\/forget\/src\/__tests__\/fixtures\/compiler\/for-of-simple.js\nnew file mode 100644\nindex 0000000000..b708b1b3b9\n--- \/dev\/null\n+++ b\/compiler\/forget\/src\/__tests__\/fixtures\/compiler\/for-of-simple.js\n@@ -0,0 +1,8 @@\n+function Component() {\n+ let x = [];\n+ let items = [0, 1, 2];\n+ for (const ii of items) {\n+ x.push(ii * 2);\n+ }\n+ return x;\n+}\ndiff --git a\/compiler\/forget\/src\/__tests__\/fixtures\/compiler\/ssa-for-of.expect.md b\/compiler\/forget\/src\/__tests__\/fixtures\/compiler\/ssa-for-of.expect.md\nnew file mode 100644\nindex 0000000000..00cc2a1f5a\n--- \/dev\/null\n+++ b\/compiler\/forget\/src\/__tests__\/fixtures\/compiler\/ssa-for-of.expect.md\n@@ -0,0 +1,39 @@\n+\n+## Input\n+\n+```javascript\n+function foo(cond) {\n+ let items = [];\n+ for (const item of items) {\n+ let y = 0;\n+ if (cond) {\n+ y = 1;\n+ }\n+ }\n+ return items;\n+}\n+\n+```\n+\n+## Code\n+\n+```javascript\n+function foo(cond) {\n+ const $ = React.unstable_useMemoCache(1);\n+ let t0;\n+ if ($[0] === Symbol.for(\"react.memo_cache_sentinel\")) {\n+ t0 = [];\n+ $[0] = t0;\n+ } else {\n+ t0 = $[0];\n+ }\n+ const items = t0;\n+ for (const item of items) {\n+ if (cond) {\n+ }\n+ }\n+ return items;\n+}\n+\n+```\n+ \n\\ No newline at end of file\ndiff --git a\/compiler\/forget\/src\/__tests__\/fixtures\/compiler\/error.ssa-for-of.js b\/compiler\/forget\/src\/__tests__\/fixtures\/compiler\/ssa-for-of.js\nsimilarity index 100%\nrename from compiler\/forget\/src\/__tests__\/fixtures\/compiler\/error.ssa-for-of.js\nrename to compiler\/forget\/src\/__tests__\/fixtures\/compiler\/ssa-for-of.js\n","parents":["1e2df5bdbb4e68996bb787a584ca47e9e597e206"],"files":[{"path":"compiler\/forget\/src\/HIR\/BuildHIR.ts","status":"M"},{"path":"compiler\/forget\/src\/HIR\/HIR.ts","status":"M"},{"path":"compiler\/forget\/src\/HIR\/HIRBuilder.ts","status":"M"},{"path":"compiler\/forget\/src\/HIR\/PrintHIR.ts","status":"M"},{"path":"compiler\/forget\/src\/HIR\/visitors.ts","status":"M"},{"path":"compiler\/forget\/src\/Inference\/InferReferenceEffects.ts","status":"M"},{"path":"compiler\/forget\/src\/Optimization\/DeadCodeElimination.ts","status":"M"},{"path":"compiler\/forget\/src\/ReactiveScopes\/BuildReactiveFunction.ts","status":"M"},{"path":"compiler\/forget\/src\/ReactiveScopes\/CodegenReactiveFunction.ts","status":"M"},{"path":"compiler\/forget\/src\/ReactiveScopes\/FlattenReactiveLoops.ts","status":"M"},{"path":"compiler\/forget\/src\/ReactiveScopes\/InferReactiveScopeVariables.ts","status":"M"},{"path":"compiler\/forget\/src\/ReactiveScopes\/PrintReactiveFunction.ts","status":"M"},{"path":"compiler\/forget\/src\/ReactiveScopes\/PropagateScopeDependencies.ts","status":"M"},{"path":"compiler\/forget\/src\/ReactiveScopes\/PruneNonEscapingScopes.ts","status":"M"},{"path":"compiler\/forget\/src\/ReactiveScopes\/visitors.ts","status":"M"},{"path":"compiler\/forget\/src\/SSA\/LeaveSSA.ts","status":"M"},{"path":"compiler\/forget\/src\/TypeInference\/InferTypes.ts","status":"M"},{"path":"compiler\/forget\/src\/Utils\/VisualizeHIRMermaid.ts","status":"M"},{"path":"compiler\/forget\/src\/__tests__\/fixtures\/compiler\/error.ssa-for-of.expect.md","status":"D"},{"path":"compiler\/forget\/src\/__tests__\/fixtures\/compiler\/error.todo-kitchensink.expect.md","status":"M"},{"path":"compiler\/forget\/src\/__tests__\/fixtures\/compiler\/error.todo-kitchensink.js","status":"M"},{"path":"compiler\/forget\/src\/__tests__\/fixtures\/compiler\/for-of-break.expect.md","status":"A"},{"path":"compiler\/forget\/src\/__tests__\/fixtures\/compiler\/for-of-break.js","status":"A"},{"path":"compiler\/forget\/src\/__tests__\/fixtures\/compiler\/for-of-conditional-break.expect.md","status":"A"},{"path":"compiler\/forget\/src\/__tests__\/fixtures\/compiler\/for-of-conditional-break.js","status":"A"},{"path":"compiler\/forget\/src\/__tests__\/fixtures\/compiler\/for-of-continue.expect.md","status":"A"},{"path":"compiler\/forget\/src\/__tests__\/fixtures\/compiler\/for-of-continue.js","status":"A"},{"path":"compiler\/forget\/src\/__tests__\/fixtures\/compiler\/for-of-destructure.expect.md","status":"A"},{"path":"compiler\/forget\/src\/__tests__\/fixtures\/compiler\/for-of-destructure.js","status":"A"},{"path":"compiler\/forget\/src\/__tests__\/fixtures\/compiler\/for-of-mutate.expect.md","status":"A"},{"path":"compiler\/forget\/src\/__tests__\/fixtures\/compiler\/for-of-mutate.js","status":"A"},{"path":"compiler\/forget\/src\/__tests__\/fixtures\/compiler\/for-of-simple.expect.md","status":"A"},{"path":"compiler\/forget\/src\/__tests__\/fixtures\/compiler\/for-of-simple.js","status":"A"},{"path":"compiler\/forget\/src\/__tests__\/fixtures\/compiler\/ssa-for-of.expect.md","status":"A"},{"previousPath":"compiler\/forget\/src\/__tests__\/fixtures\/compiler\/error.ssa-for-of.js","path":"compiler\/forget\/src\/__tests__\/fixtures\/compiler\/ssa-for-of.js","status":"R100"}]}

dillon1000/react

Files changed