feat: 配列/Mapリテラル糖衣構文の実装とネームスペース解決の改善計画

- ArrayLiteral/MapLiteralのAST定義追加
- パーサーで[...]と{...}構文をサポート
- MIR Builderでnew Box() + push/setへのdesugaring実装
- テストケースとスモークスクリプト追加
- CURRENT_TASK.mdにネームスペース解決Phase-1計画を追記
- 3段階解決順序（ローカル→エイリアス→プラグイン）の設計合意

CURRENT_TASK.md

@@ -5,6 +5,21 @@ TL;DR
 - PyVM は意味論の参照実行器（開発補助）。llvmlite は AOT/検証。配布やバンドル化は後回し（基礎固めが先）。
 
 What Changed (today)
+- リファクタリング一式 完了（Runner/LLVM/MIR Builder の分割第2弾まで）。機能差分なしで整理のみ。
+- Phase‑15（自己ホスト）を再開。まずはスモークで挙動を再確認してから警告掃除へ進む方針に切り替え。
+- 決定: 先にスモーク（PyVM/自己ホスト/Bridge）を回して“緑”を確認→ その後に `ops_ext.rs` と `runner/selfhost.rs` の警告削減に着手する。
+- 構文糖衣の導入計画（A案）を承認: Stage‑1 で配列リテラル（[a,b,c]）を追加（IR変更なし、デシュガリング）。
+
+Quick Next (today)
+- 短時間スモーク優先（挙動の健全性を早期確認）：
+  - `source tools/dev_env.sh pyvm`
+  - `NYASH_VM_USE_PY=1 ./tools/pyvm_stage2_smoke.sh`（参照実行器・意味論確認）
+  - `NYASH_USE_NY_COMPILER=1 ./tools/selfhost_stage2_smoke.sh`（自己ホスト直）
+  - `NYASH_USE_NY_COMPILER=1 ./tools/selfhost_stage2_bridge_smoke.sh`（自己ホスト→JSON→PyVM）
+  - 任意: `./tools/selfhost_stage3_accept_smoke.sh`（Stage‑3 受理のみ確認）
+- スモークが緑なら、警告の削減に移行：
+  - `src/jit/lower/core/ops_ext.rs`（未使用・到達不能/冗長の解消、保存スロットの一貫化）
+  - `src/runner/selfhost.rs`（到達不能の除去、変数寿命の短縮、細かな `let`/`mut` 是正）
 - ParserBox 強化（Stage‑2 完了 + Stage‑3 受理を追加）
   - 進捗ガード（parse_program2/parse_block2/parse_stmt2）。
   - Stage‑2 受理一式: 単項/二項/比較/論理/呼出/メソッド/引数/if/else/loop/using/local/return/new。
@@ -64,6 +79,22 @@ Notes / Policies
 - Bridge は JSON v0 → MIR 降下で PHI を生成（Phase‑15 中は現行方式を維持）。
 - 配布/バンドル/EXE 化は任意の実験導線として維持（Phase‑15 の主目的外）。
 
+Smoke Snapshot (2025‑09‑15)
+- 修正: `runner/dispatch.rs` に `vm` 分岐が欠落しており `--backend vm` が interpreter にフォールバックしていたため、PyVM スモークが作動せず。分岐を追加して復旧済み。
+- PyVM Stage‑2 部分結果:
+  - PASS: string ops basic, me method call
+  - FAIL: loop/if/phi → 出力 `sum=4`（期待 `sum=9`）
+    - 原因分析: ループ内 if の merge で `sum` の Phi 正規化が入らず、latch 側スナップショットが else 系の一時値を優先（`16`）しうる構造。`LoopBuilder::build_statement(If)` が `normalize_if_else_phi` 相当を呼ばず、変数マップが φ 統合されていない。
+    - 対応方針（最小修正）:
+      - LoopBuilder の If 降下で merge 到達時に「両枝が同一変数に代入」の場合は `phi(dst=[then,else])` を emit→その φ を対象変数に bind。
+      - latch スナップショットはこの φ 後の変数マップで採取する。
+      - 代替（短期）: Builder 側の `normalize_if_else_phi` を呼ぶ薄いフックを設けて流用。
+
+Fixes Applied (2025‑09‑15)
+- LoopBuilder If 降下に φ 正規化を追加（両枝代入の変数を merge 時に φ で束ねて再束縛）。
+- PyVM φ 解決ロジックを安定化（incoming を [value, pred] 形に限定し、[pred, value] の曖昧推測を削除）。偶然一致による誤選択を排除。
+- これにより `tools/pyvm_stage2_smoke.sh` は全 PASS を確認済み。
+
 Refactor Candidates (early plan)
 - runner/mod.rs（~70K chars）: “runner pipeline” を用途別に分割（TODO #15）
   - runner/pipeline.rs（入力正規化/using解決/環境注入）
@@ -91,3 +122,38 @@ Recommended Next (short list)
   - `builder/vars.rs` に SSA 変数正規化の小物を段階追加（変数名再束縛/スコープ終端の型ヒント伝搬など）。
 - Runner（仕上げ）
   - `mod.rs` の残置ヘルパ（usingの候補提示・環境注入ログ）を `pipeline/dispatch` へ集約し、`mod.rs` を最小のオーケストレーションに。
+  - Namespaces Phase‑1（実装着手）: BoxIndex 構築・3段階解決・toml aliases・曖昧エラー改善・トレース
+
+Array/Map Literals Plan（Syntax Sugar）
+- Stage‑1: Array literal `[e1, e2, ...]` を実装（ゲート: `NYASH_SYNTAX_SUGAR_LEVEL=basic|full` または `NYASH_ENABLE_ARRAY_LITERAL=1`）。
+  - Lowering: `new ArrayBox()` → 各要素を評価 → `.push(elem)` を左から右に順に発行 → 最後に配列値を返す。
+  - 末尾カンマ許可。
+  - スモーク: `apps/tests/array_literal_basic.nyash`（size/順序/副作用1回性）。
+- Stage‑2: Map literal `{ "k": v, ... }`（文字列キー限定）を実装（ゲート: `NYASH_SYNTAX_SUGAR_LEVEL=basic|full` or `NYASH_ENABLE_MAP_LITERAL=1`）。
+  - Lowering: `new MapBox()` → 各ペアを評価 → `.set("k", v)` を左から右に順に発行 → 最後に map 値を返す。
+  - 末尾カンマ許可。識別子キー糖 `{name: v}` は次フェーズ。
+  - スモーク: `apps/tests/map_literal_basic.nyash`（size/get/順序検証）。
+- Stage‑3: 識別子キー糖 `{name: v}` と末尾カンマを強化（任意）。
+
+Gates / Semantics
+- 左から右で評価（一度だけ）。push/set 失敗は即時伝播（既存 BoxCall 規約に追従）。
+- IR 変更なし（BoxCall/MethodCall のみ）。将来 `with_capacity(n)` 最適化は任意で追加。
+
+Decision Log (2025‑09‑15)
+- Q: 警告削減（`ops_ext.rs` / `selfhost.rs`）を先にやる？それとも挙動スモークを先に回す？
+- A: スモークを先に実施。理由は以下。
+  - リファクタ直後は回帰検出を最優先（PyVM/自己ホスト/Bridge の3レーンで即座に検証）。
+  - 警告削減は挙動非変化を原則とするが、微妙なスコープや保存スロットの触りが混入し得るため、先に“緑”を固める。
+Namespaces / Using（計画合意）
+- 3段階の解決順（決定性）: 1) ローカル/コアボックス → 2) エイリアス（nyash.toml/needs） → 3) プラグイン（短名/qualified）
+- 曖昧時はエラー＋候補提示。qualified または alias を要求（自動推測はしない）。
+- モード切替: Relaxed（既定）/Strict（`NYASH_PLUGIN_REQUIRE_PREFIX=1` or toml `[plugins] require_prefix=true`）
+- needs 糖衣は using の同義（Runner で alias 登録）。`needs plugin.network.HttpClient as HttpClient` 等。
+- Plugins は統合名前空間（短名はユニーク時のみ）。qualified `network.HttpClient` を常時許可。
+- nyash.toml（MVP）: `[imports]`/`[aliases]`，`[plugins.<name>] { path, prefix, require_prefix, expose_short_names }`
+- Index とキャッシュ（Runner）:
+  - BoxIndex: `local_boxes`, `plugin_boxes`, `aliases` を保持
+  - `RESOLVE_CACHE`（thread‑local）で同一解決の再計算を回避
+  - `NYASH_RESOLVE_TRACE=1` で解決過程をログ出力
+
+  - スモークが緑＝基礎健全性確認後に、静的ノイズの除去を安全に一気通貫で行う。

apps/tests/array_literal_basic.nyash

@@ -0,0 +1,11 @@
+static box Main {
+  main(args) {
+    local console = new ConsoleBox()
+    local x = 1
+    // array literal sugar
+    local arr = [x, 2, 3]
+    console.println(arr.size())
+    return 0
+  }
+}
+

apps/tests/map_literal_basic.nyash

@@ -0,0 +1,11 @@
+static box Main {
+  main(args) {
+    local console = new ConsoleBox()
+    // map literal sugar (string keys)
+    local m = {"name": "Alice", "age": 25}
+    console.println(m.size())
+    console.println(m.get("name"))
+    return 0
+  }
+}
+

apps/tests/map_literal_ident_key.nyash

@@ -0,0 +1,10 @@
+static box Main {
+  main(args) {
+    local console = new ConsoleBox()
+    local m = {name: "A", age: 2,}
+    console.println(m.size())
+    console.println(m.get("name"))
+    return 0
+  }
+}
+

docs/reference/language/EBNF.md

@@ -24,6 +24,10 @@ factor    := INT
            | IDENT call_tail*
            | '(' expr ')'
            | 'new' IDENT '(' args? ')'
+           | '[' args? ']'           ; Array literal (Stage‑1 sugar, gated)
+           | '{' map_entries? '}'    ; Map literal (Stage‑2 sugar, gated)
+
+map_entries := (STRING | IDENT) ':' expr (',' (STRING | IDENT) ':' expr)* [',']
 
 call_tail := '.' IDENT '(' args? ')'   ; method
            | '(' args? ')'             ; function call
@@ -35,4 +39,6 @@ Notes
 - Short-circuit: '&&' and '||' must not evaluate the RHS when not needed.
 - Unary minus has higher precedence than '*' and '/'.
 - IDENT names consist of [A-Za-z_][A-Za-z0-9_]*
-
+- Array literal is enabled when syntax sugar is on (NYASH_SYNTAX_SUGAR_LEVEL=basic|full) or when NYASH_ENABLE_ARRAY_LITERAL=1 is set.
+- Map literal is enabled when syntax sugar is on (NYASH_SYNTAX_SUGAR_LEVEL=basic|full) or when NYASH_ENABLE_MAP_LITERAL=1 is set.
+- Identifier keys (`{name: v}`) are Stage‑3 and require either NYASH_SYNTAX_SUGAR_LEVEL=full or NYASH_ENABLE_MAP_IDENT_KEY=1.

docs/reference/language/using.md

@@ -1,4 +1,4 @@
-# using — Imports and Namespaces (Phase 15)
+# using — Imports and Namespaces (Phase 15+)
 
 Status: Accepted (Runner‑side resolution). Selfhost parser accepts using as no‑op and attaches `meta.usings` for future use.
 
@@ -9,6 +9,50 @@ Policy
   - Registers modules into an internal registry for path/namespace hints.
 - Selfhost compiler (Ny→JSON v0) collects using lines and emits `meta.usings` when present. The bridge currently ignores this meta field.
 
+## Namespace Resolution (Runner‑side)
+- Goal: keep IR/VM/JIT untouched. All resolution happens in Runner/Registry.
+- Default search order (3 stages, deterministic):
+  1) Local/Core Boxes (nyrt)
+  2) Aliases (nyash.toml [imports] / `needs … as …`)
+  3) Plugins (short name if unique, otherwise qualified `pluginName.BoxName`)
+- On ambiguity: error with candidates and remediation (qualify or define alias).
+- Modes:
+  - Relaxed (default): short names allowed when unique.
+  - Strict: require plugin prefix (env `NYASH_PLUGIN_REQUIRE_PREFIX=1` or nyash.toml `[plugins] require_prefix=true`).
+- Aliases:
+  - nyash.toml `[imports] HttpClient = "network.HttpClient"`
+  - needs sugar: `needs plugin.network.HttpClient as HttpClient` (file‑scoped alias)
+
+## Plugins
+- Unified namespace with Boxes. Prefer short names when unique.
+- Qualified form: `network.HttpClient`
+- Per‑plugin control (nyash.toml): `prefix`, `require_prefix`, `expose_short_names`
+
+## `needs` sugar (optional)
+- Treated as a synonym to `using` on the Runner side; registers aliases only.
+- Examples: `needs utils.StringHelper`, `needs plugin.network.HttpClient as HttpClient`, `needs plugin.network.*`
+
+## nyash.toml keys (MVP)
+- `[imports]`/`[aliases]`: short name → fully qualified
+- `[plugins.<name>]`: `path`, `prefix`, `require_prefix`, `expose_short_names`
+
+## Index and Cache (Runner)
+- Build a Box index once per run to make resolution fast and predictable:
+```
+struct BoxIndex {
+    local_boxes: HashMap<String, PathBuf>,
+    plugin_boxes: HashMap<String, Vec<PluginBox>>,
+    aliases: HashMap<String, String>,
+}
+```
+- Maintain a small resolve cache per thread:
+```
+thread_local! {
+    static RESOLVE_CACHE: RefCell<HashMap<String, ResolvedBox>> = /* ... */;
+}
+```
+- Trace: `NYASH_RESOLVE_TRACE=1` prints resolution steps (for debugging/CI logs).
+
 Syntax
 - Namespace: `using core.std` or `using core.std as Std`
 - File path: `using "apps/examples/string_p0.nyash" as Strings`
@@ -34,6 +78,28 @@ static box Main {
 }
 ```
 
+Qualified/Plugins/Aliases examples
+```nyash
+# nyash.toml
+[plugins.network]
+path = "plugins/network.so"
+prefix = "network"
+require_prefix = false
+
+[imports]
+HttpClient = "network.HttpClient"
+
+# code
+needs plugin.network.HttpClient as HttpClient
+
+static box Main {
+  main(args) {
+    let a = new HttpClient()         # alias
+    let b = new network.HttpClient() # qualified
+  }
+}
+```
+
 Runner Configuration
 - Enable using pre‑processing: `NYASH_ENABLE_USING=1`
 - Selfhost pipeline keeps child stdout quiet and extracts JSON only: `NYASH_JSON_ONLY=1` (set by Runner automatically for child)
@@ -42,4 +108,3 @@ Runner Configuration
 Notes
 - Phase 15 keeps resolution in the Runner to minimize parser complexity. Future phases may leverage `meta.usings` for compiler decisions.
 - Unknown fields in the top‑level JSON (like `meta`) are ignored by the current bridge.
-

src/ast.rs

@@ -201,6 +201,7 @@ pub enum ExpressionNode {
         else_expr: Box<ASTNode>,
         span: Span,
     },
+    // (Stage‑2 sugar for literals is represented in unified ASTNode, not here)
 }
 
 /// 文ノード - 実行可能なアクション  
@@ -476,6 +477,16 @@ pub enum ASTNode {
         else_expr: Box<ASTNode>,
         span: Span,
     },
+    /// 配列リテラル（糖衣）: [e1, e2, ...]
+    ArrayLiteral {
+        elements: Vec<ASTNode>,
+        span: Span,
+    },
+    /// マップリテラル（糖衣）: { "k": v, ... } （Stage‑2: 文字列キー限定）
+    MapLiteral {
+        entries: Vec<(String, ASTNode)>,
+        span: Span,
+    },
     
     /// 無名関数（最小P1: 値としてのみ。呼び出しは未対応）
     Lambda {
@@ -708,6 +719,8 @@ impl ASTNode {
             ASTNode::QMarkPropagate { .. } => "QMarkPropagate",
             ASTNode::PeekExpr { .. } => "PeekExpr",
             ASTNode::Lambda { .. } => "Lambda",
+            ASTNode::ArrayLiteral { .. } => "ArrayLiteral",
+            ASTNode::MapLiteral { .. } => "MapLiteral",
         }
     }
     
@@ -740,6 +753,8 @@ impl ASTNode {
             ASTNode::PeekExpr { .. } => ASTNodeType::Expression,
             ASTNode::QMarkPropagate { .. } => ASTNodeType::Expression,
             ASTNode::Lambda { .. } => ASTNodeType::Expression,
+            ASTNode::ArrayLiteral { .. } => ASTNodeType::Expression,
+            ASTNode::MapLiteral { .. } => ASTNodeType::Expression,
             
             // Statement nodes - 実行可能なアクション
             ASTNode::Program { .. } => ASTNodeType::Statement, // プログラム全体
@@ -903,6 +918,12 @@ impl ASTNode {
             ASTNode::Lambda { params, body, .. } => {
                 format!("Lambda({} params, {} statements)", params.len(), body.len())
             }
+            ASTNode::ArrayLiteral { elements, .. } => {
+                format!("ArrayLiteral({} elements)", elements.len())
+            }
+            ASTNode::MapLiteral { entries, .. } => {
+                format!("MapLiteral({} entries)", entries.len())
+            }
         }
     }
     
@@ -947,6 +968,8 @@ impl ASTNode {
             ASTNode::PeekExpr { span, .. } => *span,
             ASTNode::QMarkPropagate { span, .. } => *span,
             ASTNode::Lambda { span, .. } => *span,
+            ASTNode::ArrayLiteral { span, .. } => *span,
+            ASTNode::MapLiteral { span, .. } => *span,
         }
     }
 }

src/backend/vm_exec.rs

@@ -135,9 +135,9 @@ impl VM {
 
     /// Execute a single function
     pub(super) fn execute_function(&mut self, function: &MirFunction) -> Result<VMValue, VMError> {
-        use crate::box_trait::{StringBox, IntegerBox, BoolBox, VoidBox};
+        // unused: local downcasts not required here
         use crate::runtime::global_hooks;
-        use crate::instance_v2::InstanceBox;
+        // use crate::instance_v2::InstanceBox; // not used in this path
         use super::control_flow;
 
         self.current_function = Some(function.signature.name.clone());

src/backend/vm_instructions/boxcall.rs

@@ -1,4 +1,3 @@
-use crate::box_trait::NyashBox;
 use crate::mir::ValueId;
 use crate::backend::vm::ControlFlow;
 use crate::backend::{VM, VMError, VMValue};
@@ -7,7 +6,7 @@ impl VM {
     /// Small helpers to reduce duplication in vtable stub paths.
     #[inline]
     fn vmvalue_to_box(val: &VMValue) -> Box<dyn crate::box_trait::NyashBox> {
-        use crate::box_trait::{NyashBox, StringBox as SBox, IntegerBox as IBox, BoolBox as BBox};
+        use crate::box_trait::{StringBox as SBox, IntegerBox as IBox, BoolBox as BBox};
         match val {
             VMValue::Integer(i) => Box::new(IBox::new(*i)),
             VMValue::String(s) => Box::new(SBox::new(s)),
@@ -900,3 +899,4 @@ impl VM {
         Ok(None)
     }
 }
+use crate::box_trait::NyashBox;

src/backend/vm_instructions/core.rs

@@ -1,5 +1,5 @@
 use crate::mir::{ConstValue, BinaryOp, CompareOp, UnaryOp, ValueId, BasicBlockId, TypeOpKind, MirType};
-use crate::box_trait::{NyashBox, BoolBox, VoidBox};
+use crate::box_trait::{BoolBox, VoidBox};
 use crate::boxes::ArrayBox;
 use std::sync::Arc;
 use crate::backend::vm::ControlFlow;

src/backend/vm_state.rs

@@ -12,7 +12,7 @@ use crate::mir::{BasicBlockId, ValueId};
 use crate::runtime::NyashRuntime;
 use crate::scope_tracker::ScopeTracker;
 use std::collections::HashMap;
-use std::time::Instant;
+// use std::time::Instant; // not used in this module
 
 impl VM {
     fn jit_threshold_from_env() -> u32 {

src/interpreter/expressions/builtins.rs

@@ -47,7 +47,7 @@ impl NyashInterpreter {
             }
             "MathBox" => {
                 if let Ok(reg) = self.runtime.box_registry.lock() {
-                    if let Ok(b) = reg.create_box("MathBox", &[]) {
+                    if let Ok(_b) = reg.create_box("MathBox", &[]) {
                         // Note: execute_math_method expects builtin MathBox; plugin path should route via VM/BoxCall in new pipeline.
                         // Here we simply return void; method paths should prefer plugin invoke in VM.
                         return Ok(Box::new(VoidBox::new()));

src/jit/lower/core.rs

@@ -1,5 +1,5 @@
-use crate::mir::{MirFunction, MirInstruction, ConstValue, BinaryOp, CompareOp, ValueId};
-use super::builder::{IRBuilder, BinOpKind, CmpKind};
+use crate::mir::{MirFunction, MirInstruction, ConstValue, ValueId};
+use super::builder::{IRBuilder, BinOpKind};
 
 mod analysis;
 mod cfg;

src/jit/lower/core/analysis.rs

@@ -1,9 +1,8 @@
-use std::collections::{HashMap, HashSet, BTreeSet};
+use std::collections::HashSet;
 
 use crate::mir::{BasicBlockId, MirFunction, MirInstruction, ValueId};
 
-use super::super::builder::IRBuilder;
-use super::super::core_ops; // ensure module link remains
+// removed unused imports
 use super::LowerCore;
 
 impl LowerCore {
@@ -114,4 +113,3 @@ impl LowerCore {
         }
     }
 }
-

src/llvm_py/pyvm/vm.py

@@ -127,6 +127,9 @@ class PyVM:
                     # incoming: prefer [[vid, pred_bid]], but accept [pred_bid, vid] robustly
                     incoming = inst.get("incoming", [])
                     chosen: Any = None
+                    dbg = os.environ.get('NYASH_PYVM_DEBUG_PHI') == '1'
+                    if dbg:
+                        print(f"[pyvm.phi] prev={prev} incoming={incoming}")
                     for pair in incoming:
                         if not isinstance(pair, (list, tuple)) or len(pair) < 2:
                             continue
@@ -134,10 +137,8 @@ class PyVM:
                         # Case 1: [vid, pred]
                         if prev is not None and int(b) == int(prev) and int(a) in regs:
                             chosen = regs.get(int(a))
-                            break
-                        # Case 2: [pred, vid]
-                        if prev is not None and int(a) == int(prev) and int(b) in regs:
-                            chosen = regs.get(int(b))
+                            if dbg:
+                                print(f"[pyvm.phi] case1 match: use v{a} from pred {b} -> {chosen}")
                             break
                     if chosen is None and incoming:
                         # Fallback to first element that resolves to a known vid
@@ -147,8 +148,9 @@ class PyVM:
                             a, b = pair[0], pair[1]
                             if int(a) in regs:
                                 chosen = regs.get(int(a)); break
-                            if int(b) in regs:
-                                chosen = regs.get(int(b)); break
+                            # Do not try to resolve by assuming [pred, vid] — avoid false matches
+                    if dbg:
+                        print(f"[pyvm.phi] chosen={chosen}")
                     self._set(regs, inst.get("dst"), chosen)
                     i += 1
                     continue

src/mir/builder.rs

@@ -487,6 +487,17 @@ impl MirBuilder {
                 self.build_new_expression(class.clone(), arguments.clone())
             },
             
+            ASTNode::ArrayLiteral { elements, .. } => {
+                // Lower: new ArrayBox(); for each elem: .push(elem)
+                let arr_id = self.value_gen.next();
+                self.emit_instruction(MirInstruction::NewBox { dst: arr_id, box_type: "ArrayBox".to_string(), args: vec![] })?;
+                for e in elements {
+                    let v = self.build_expression(e)?;
+                    self.emit_instruction(MirInstruction::BoxCall { dst: None, box_val: arr_id, method: "push".to_string(), method_id: None, args: vec![v], effects: super::EffectMask::MUT })?;
+                }
+                Ok(arr_id)
+            },
+            
             // Phase 7: Async operations
             ASTNode::Nowait { variable, expression, .. } => {
                 self.build_nowait_statement(variable.clone(), *expression.clone())

src/mir/builder/exprs.rs

@@ -114,6 +114,28 @@ impl super::MirBuilder {
             ASTNode::New { class, arguments, .. } =>
                 self.build_new_expression(class.clone(), arguments.clone()),
 
+            ASTNode::ArrayLiteral { elements, .. } => {
+                let arr_id = self.value_gen.next();
+                self.emit_instruction(MirInstruction::NewBox { dst: arr_id, box_type: "ArrayBox".to_string(), args: vec![] })?;
+                for e in elements {
+                    let v = self.build_expression_impl(e)?;
+                    self.emit_instruction(MirInstruction::BoxCall { dst: None, box_val: arr_id, method: "push".to_string(), method_id: None, args: vec![v], effects: super::EffectMask::MUT })?;
+                }
+                Ok(arr_id)
+            }
+            ASTNode::MapLiteral { entries, .. } => {
+                let map_id = self.value_gen.next();
+                self.emit_instruction(MirInstruction::NewBox { dst: map_id, box_type: "MapBox".to_string(), args: vec![] })?;
+                for (k, expr) in entries {
+                    // const string key
+                    let k_id = self.value_gen.next();
+                    self.emit_instruction(MirInstruction::Const { dst: k_id, value: ConstValue::String(k) })?;
+                    let v_id = self.build_expression_impl(expr)?;
+                    self.emit_instruction(MirInstruction::BoxCall { dst: None, box_val: map_id, method: "set".to_string(), method_id: None, args: vec![k_id, v_id], effects: super::EffectMask::MUT })?;
+                }
+                Ok(map_id)
+            }
+
             ASTNode::Nowait { variable, expression, .. } =>
                 self.build_nowait_statement(variable.clone(), *expression.clone()),
 

src/mir/loop_builder.rs

@@ -42,6 +42,29 @@ pub struct LoopBuilder<'a> {
     continue_snapshots: Vec<(BasicBlockId, HashMap<String, ValueId>)>,
 }
 
+// Local copy: detect a variable name assigned within an AST fragment
+fn extract_assigned_var_local(ast: &ASTNode) -> Option<String> {
+    match ast {
+        ASTNode::Assignment { target, .. } => {
+            if let ASTNode::Variable { name, .. } = target.as_ref() { Some(name.clone()) } else { None }
+        }
+        ASTNode::Program { statements, .. } => statements.last().and_then(|st| extract_assigned_var_local(st)),
+        ASTNode::If { then_body, else_body, .. } => {
+            let then_prog = ASTNode::Program { statements: then_body.clone(), span: crate::ast::Span::unknown() };
+            let tvar = extract_assigned_var_local(&then_prog);
+            let evar = else_body.as_ref().and_then(|eb| {
+                let ep = ASTNode::Program { statements: eb.clone(), span: crate::ast::Span::unknown() };
+                extract_assigned_var_local(&ep)
+            });
+            match (tvar, evar) {
+                (Some(tv), Some(ev)) if tv == ev => Some(tv),
+                _ => None,
+            }
+        }
+        _ => None,
+    }
+}
+
 impl<'a> LoopBuilder<'a> {
     /// 新しいループビルダーを作成
     pub fn new(parent: &'a mut super::builder::MirBuilder) -> Self {
@@ -325,6 +348,10 @@ impl<'a> LoopBuilder<'a> {
                 let merge_bb = self.new_block();
                 self.emit_branch(cond_val, then_bb, else_bb)?;
 
+                // Capture pre-if variable map (used for phi normalization)
+                let pre_if_var_map = self.get_current_variable_map();
+                let pre_then_var_value = pre_if_var_map.clone();
+
                 // then
                 self.set_current_block(then_bb)?;
                 for s in then_body.iter().cloned() {
@@ -338,6 +365,7 @@ impl<'a> LoopBuilder<'a> {
                     };
                     if terminated { break; }
                 }
+                let then_var_map_end = self.get_current_variable_map();
                 // Only jump to merge if not already terminated (e.g., continue/break)
                 {
                     let cur_id = self.current_block()?;
@@ -351,7 +379,8 @@ impl<'a> LoopBuilder<'a> {
 
                 // else
                 self.set_current_block(else_bb)?;
-                if let Some(es) = else_body {
+                let mut else_var_map_end_opt: Option<std::collections::HashMap<String, super::ValueId>> = None;
+                if let Some(es) = else_body.clone() {
                     for s in es.into_iter() {
                         let _ = self.build_statement(s)?;
                         let cur_id = self.current_block()?;
@@ -362,6 +391,7 @@ impl<'a> LoopBuilder<'a> {
                         };
                         if terminated { break; }
                     }
+                    else_var_map_end_opt = Some(self.get_current_variable_map());
                 }
                 {
                     let cur_id = self.current_block()?;
@@ -375,6 +405,29 @@ impl<'a> LoopBuilder<'a> {
 
                 // Continue at merge
                 self.set_current_block(merge_bb)?;
+                // If both branches assign the same variable, emit phi and bind it
+                let then_prog = ASTNode::Program { statements: then_body.clone(), span: crate::ast::Span::unknown() };
+                let assigned_then = extract_assigned_var_local(&then_prog);
+                let assigned_else = else_body.as_ref().and_then(|es| {
+                    let ep = ASTNode::Program { statements: es.clone(), span: crate::ast::Span::unknown() };
+                    extract_assigned_var_local(&ep)
+                });
+                if let Some(var_name) = assigned_then {
+                    let else_assigns_same = assigned_else.as_ref().map(|s| s == &var_name).unwrap_or(false);
+                    let then_value_for_var = then_var_map_end.get(&var_name).copied();
+                    let else_value_for_var = if else_assigns_same {
+                        else_var_map_end_opt.as_ref().and_then(|m| m.get(&var_name).copied())
+                    } else {
+                        pre_then_var_value.get(&var_name).copied()
+                    };
+                    if let (Some(tv), Some(ev)) = (then_value_for_var, else_value_for_var) {
+                        let phi_id = self.new_value();
+                        self.emit_phi_at_block_start(merge_bb, phi_id, vec![(then_bb, tv), (else_bb, ev)])?;
+                        // Reset to pre-if map and bind the phi result
+                        self.parent_builder.variable_map = pre_if_var_map.clone();
+                        self.parent_builder.variable_map.insert(var_name, phi_id);
+                    }
+                }
                 let void_id = self.new_value();
                 self.emit_const(void_id, ConstValue::Void)?;
                 Ok(void_id)

src/parser/expressions.rs

@@ -631,9 +631,71 @@ impl NyashParser {
         Ok(expr)
     }
     
-    /// 基本式をパース: リテラル、変数、括弧、this、new
+    /// 基本式をパース: リテラル、変数、括弧、this、new、配列リテラル（糖衣）
     fn parse_primary(&mut self) -> Result<ASTNode, ParseError> {
         match &self.current_token().token_type {
+            TokenType::LBRACK => {
+                // Array literal: [e1, e2, ...] (sugar)
+                let sugar_on = crate::parser::sugar_gate::is_enabled()
+                    || std::env::var("NYASH_ENABLE_ARRAY_LITERAL").ok().as_deref() == Some("1");
+                if !sugar_on {
+                    let line = self.current_token().line;
+                    return Err(ParseError::UnexpectedToken {
+                        found: self.current_token().token_type.clone(),
+                        expected: "enable NYASH_SYNTAX_SUGAR_LEVEL=basic|full or NYASH_ENABLE_ARRAY_LITERAL=1".to_string(),
+                        line,
+                    });
+                }
+                self.advance(); // consume '['
+                let mut elems: Vec<ASTNode> = Vec::new();
+                while !self.match_token(&TokenType::RBRACK) && !self.is_at_end() {
+                    must_advance!(self, _unused, "array literal element parsing");
+                    let el = self.parse_expression()?;
+                    elems.push(el);
+                    if self.match_token(&TokenType::COMMA) { self.advance(); }
+                }
+                self.consume(TokenType::RBRACK)?;
+                Ok(ASTNode::ArrayLiteral { elements: elems, span: Span::unknown() })
+            }
+            TokenType::LBRACE => {
+                // Map literal (Stage‑2, string keys only)
+                let sugar_on = crate::parser::sugar_gate::is_enabled()
+                    || std::env::var("NYASH_ENABLE_MAP_LITERAL").ok().as_deref() == Some("1");
+                if !sugar_on {
+                    let line = self.current_token().line;
+                    return Err(ParseError::UnexpectedToken {
+                        found: self.current_token().token_type.clone(),
+                        expected: "enable NYASH_SYNTAX_SUGAR_LEVEL=basic|full or NYASH_ENABLE_MAP_LITERAL=1".to_string(),
+                        line,
+                    });
+                }
+                self.advance(); // consume '{'
+                let mut entries: Vec<(String, ASTNode)> = Vec::new();
+                let sugar_level = std::env::var("NYASH_SYNTAX_SUGAR_LEVEL").ok();
+                let ident_key_on = std::env::var("NYASH_ENABLE_MAP_IDENT_KEY").ok().as_deref() == Some("1")
+                    || sugar_level.as_deref() == Some("full");
+                while !self.match_token(&TokenType::RBRACE) && !self.is_at_end() {
+                    // Key: string literal (Stage‑2) or identifier key sugar (Stage‑3; gated)
+                    let key = match &self.current_token().token_type {
+                        TokenType::STRING(s) => { let v = s.clone(); self.advance(); v }
+                        TokenType::IDENTIFIER(id) if ident_key_on => { let v = id.clone(); self.advance(); v }
+                        _ => {
+                            let line = self.current_token().line;
+                            return Err(ParseError::UnexpectedToken {
+                                found: self.current_token().token_type.clone(),
+                                expected: if ident_key_on { "string or identifier key in map literal".to_string() } else { "string key in map literal".to_string() },
+                                line,
+                            });
+                        }
+                    };
+                    self.consume(TokenType::COLON)?;
+                    let value_expr = self.parse_expression()?;
+                    entries.push((key, value_expr));
+                    if self.match_token(&TokenType::COMMA) { self.advance(); }
+                }
+                self.consume(TokenType::RBRACE)?;
+                Ok(ASTNode::MapLiteral { entries, span: Span::unknown() })
+            }
             TokenType::INCLUDE => {
                 // Allow include as an expression: include "path"
                 self.parse_include()

src/runner/dispatch.rs

@@ -86,6 +86,12 @@ pub(crate) fn execute_file_with_backend(runner: &NyashRunner, filename: &str) {
                 }
                 runner.execute_mir_mode(filename);
             }
+            "vm" => {
+                if std::env::var("NYASH_CLI_VERBOSE").ok().as_deref() == Some("1") {
+                    println!("🚀 Nyash VM Backend - Executing file: {} 🚀", filename);
+                }
+                runner.execute_vm_mode(filename);
+            }
             #[cfg(feature = "cranelift-jit")]
             "jit-direct" => {
                 if std::env::var("NYASH_CLI_VERBOSE").ok().as_deref() == Some("1") {

src/runner/mod.rs

@@ -6,20 +6,8 @@
  */
 
 use nyash_rust::cli::CliConfig;
-use nyash_rust::{
-    box_trait::{StringBox, IntegerBox, BoolBox, VoidBox, AddBox},
-    tokenizer::{NyashTokenizer},
-    ast::ASTNode,
-    parser::NyashParser,
-    interpreter::NyashInterpreter,
-    mir::{MirCompiler, MirPrinter, MirInstruction},
-    backend::VM,
-};
-use nyash_rust::runtime::{NyashRuntime, NyashRuntimeBuilder};
-use nyash_rust::interpreter::SharedState;
-use nyash_rust::box_factory::user_defined::UserDefinedBoxFactory;
-use nyash_rust::core::model::BoxDeclaration as CoreBoxDecl;
-use std::sync::Arc;
+// prune heavy unused imports here; modules import what they need locally
+// pruned unused runtime imports in this module
 
 #[cfg(feature = "wasm-backend")]
 use nyash_rust::backend::{wasm::WasmBackend, aot::AotBackend};

src/runner/modes/vm.rs

@@ -183,7 +183,7 @@ impl NyashRunner {
                 // Prefer MIR signature when available, but fall back to runtime coercions to keep VM/JIT consistent.
                 let (ety, sval) = if let Some(func) = compile_result.module.functions.get("main") {
                     use nyash_rust::mir::MirType;
-                    use nyash_rust::box_trait::{NyashBox, IntegerBox, BoolBox, StringBox};
+                    use nyash_rust::box_trait::{IntegerBox, BoolBox, StringBox};
                     use nyash_rust::boxes::FloatBox;
                     match &func.signature.return_type {
                         MirType::Float => {
@@ -272,7 +272,7 @@ impl NyashRunner {
             format!("./{}", filename)
         }
 
-        use std::collections::{HashSet, VecDeque};
+        use std::collections::HashSet;
 
         fn walk_with_state(node: &ASTNode, runtime: &NyashRuntime, stack: &mut Vec<String>, visited: &mut HashSet<String>) {
             match node {

src/runtime/plugin_loader_v2/enabled/loader.rs

@@ -1,6 +1,6 @@
-use super::types::{PluginBoxV2, PluginHandleInner, NyashTypeBoxFfi, LoadedPluginV2};
+use super::types::{PluginBoxV2, PluginHandleInner, LoadedPluginV2};
 use crate::bid::{BidResult, BidError};
-use crate::box_trait::{NyashBox, BoxCore, StringBox, IntegerBox};
+use crate::box_trait::NyashBox;
 use crate::config::nyash_toml_v2::{NyashConfigV2, LibraryDefinition};
 use std::collections::HashMap;
 use std::sync::{Arc, RwLock};

src/tokenizer.rs

@@ -94,6 +94,8 @@ pub enum TokenType {
     DoubleColon,     // :: (Parent::method) - P1用（定義のみ）
     LPAREN,          // (
     RPAREN,          // )
+    LBRACK,          // [
+    RBRACK,          // ]
     LBRACE,          // {
     RBRACE,          // }
     COMMA,           // ,
@@ -395,6 +397,14 @@ impl NyashTokenizer {
                 self.advance();
                 Ok(Token::new(TokenType::RPAREN, start_line, start_column))
             }
+            Some('[') => {
+                self.advance();
+                Ok(Token::new(TokenType::LBRACK, start_line, start_column))
+            }
+            Some(']') => {
+                self.advance();
+                Ok(Token::new(TokenType::RBRACK, start_line, start_column))
+            }
             Some('{') => {
                 self.advance();
                 Ok(Token::new(TokenType::LBRACE, start_line, start_column))
@@ -407,14 +417,7 @@ impl NyashTokenizer {
                 self.advance();
                 Ok(Token::new(TokenType::COMMA, start_line, start_column))
             }
-            Some('?') => {
-                self.advance();
-                Ok(Token::new(TokenType::QUESTION, start_line, start_column))
-            }
-            Some(':') => {
-                self.advance();
-                Ok(Token::new(TokenType::COLON, start_line, start_column))
-            }
+            // '?' and ':' are handled earlier (including variants); avoid duplicate arms
             Some('\n') => {
                 self.advance();
                 Ok(Token::new(TokenType::NEWLINE, start_line, start_column))

tools/pyvm_array_literal_smoke.sh

@@ -0,0 +1,19 @@
+#!/usr/bin/env bash
+set -euo pipefail
+
+ROOT_DIR=$(CDPATH= cd -- "$(dirname -- "$0")"/.. && pwd)
+BIN="$ROOT_DIR/target/release/nyash"
+
+if [[ ! -x "$BIN" ]]; then
+  (cd "$ROOT_DIR" && cargo build --release >/dev/null)
+fi
+
+run() {
+  NYASH_VM_USE_PY=1 NYASH_SYNTAX_SUGAR_LEVEL=basic "$BIN" --backend vm "$ROOT_DIR/apps/tests/array_literal_basic.nyash" 2>&1
+}
+
+OUT=$(run || true)
+echo "$OUT" | rg -q '^3$' && echo "✅ PyVM: array literal basic" || { echo "❌ PyVM: array literal basic"; echo "$OUT"; exit 1; }
+
+echo "Array literal smoke PASS" >&2
+

tools/pyvm_map_literal_ident_smoke.sh

@@ -0,0 +1,20 @@
+#!/usr/bin/env bash
+set -euo pipefail
+
+ROOT_DIR=$(CDPATH= cd -- "$(dirname -- "$0")"/.. && pwd)
+BIN="$ROOT_DIR/target/release/nyash"
+
+if [[ ! -x "$BIN" ]]; then
+  (cd "$ROOT_DIR" && cargo build --release >/dev/null)
+fi
+
+run() {
+  NYASH_VM_USE_PY=1 NYASH_SYNTAX_SUGAR_LEVEL=full NYASH_ENABLE_MAP_LITERAL=1 "$BIN" --backend vm "$ROOT_DIR/apps/tests/map_literal_ident_key.nyash" 2>&1
+}
+
+OUT=$(run || true)
+echo "$OUT" | rg -q '^2$' && echo "$OUT" | rg -q '^A$' \
+  && echo "✅ PyVM: map literal ident-key" || { echo "❌ PyVM: map literal ident-key"; echo "$OUT"; exit 1; }
+
+echo "Map literal ident-key smoke PASS" >&2
+

tools/pyvm_map_literal_smoke.sh

@@ -0,0 +1,20 @@
+#!/usr/bin/env bash
+set -euo pipefail
+
+ROOT_DIR=$(CDPATH= cd -- "$(dirname -- "$0")"/.. && pwd)
+BIN="$ROOT_DIR/target/release/nyash"
+
+if [[ ! -x "$BIN" ]]; then
+  (cd "$ROOT_DIR" && cargo build --release >/dev/null)
+fi
+
+run() {
+  NYASH_VM_USE_PY=1 NYASH_SYNTAX_SUGAR_LEVEL=basic NYASH_ENABLE_MAP_LITERAL=1 "$BIN" --backend vm "$ROOT_DIR/apps/tests/map_literal_basic.nyash" 2>&1
+}
+
+OUT=$(run || true)
+echo "$OUT" | rg -q '^2$' && echo "$OUT" | rg -q '^Alice$' \
+  && echo "✅ PyVM: map literal basic" || { echo "❌ PyVM: map literal basic"; echo "$OUT"; exit 1; }
+
+echo "Map literal smoke PASS" >&2
+