# Environment Variables — Quick Reference (Phase 22.1)

This document lists the environment flags introduced or used by the Phase 22.1 work. Defaults are OFF and behavior remains unchanged unless noted.

- HAKO_USING_SSOT=0|1
  - Enables the SSOT resolver gate in the runner pipeline.
  - When ON, resolution first consults the SSOT bridge (modules-only MVP). If not resolved, it falls back to the existing resolver.
  - Trace: set `NYASH_RESOLVE_TRACE=1` to see `[using/ssot]` tags.

- HAKO_USING_SSOT_HAKO=0|1
  - Optional: within the SSOT bridge, call the Hako box `UsingResolveSSOTBox.resolve(name, ctx)` via the VM.
  - MVP passes `{ modules, using_paths, cwd }` in `ctx` (modules is consulted). IO is not performed in the box.
  - Requires `nyash` binary present; guard remains OFF by default.

Relative inference (SSOT)
- Default OFF: `HAKO_USING_SSOT_RELATIVE=1` enables a minimal relative candidate synthesis (cwd → using_paths). When multiple candidates exist and `NYASH_USING_STRICT=1`, resolution delegates to legacy resolver (behavior unchanged).
 - Ambiguous list size: `HAKO_USING_SSOT_RELATIVE_AMBIG_FIRST_N=<N>` customizes how many candidates are shown in trace (default 3, bounded 1–10).

Notes on SSOT ctx (expansion plan)
- The bridge constructs a context with:
  - `modules` (Map<String,String>) — exact name → path mapping
  - `using_paths` (Array<String>) — resolution bases (MVP: hint only)
  - `cwd` (String) — caller’s directory (MVP: hint only)
- Hako box will progressively leverage `using_paths`/`cwd` for relative inference (planned; defaults remain unchanged until enabled).

- HAKO_TLV_SHIM=0|1
  - Enables an identity TLV round‑trip at the end of argument encoding for plugin calls.
  - Requires building with `--features tlv-shim` to link the optional crate `nyash-tlv`.
  - Default OFF; when OFF, the buffer is returned unchanged.

- tlv-shim (Cargo feature)
  - `cargo build --features tlv-shim` links the optional `nyash-tlv` crate.
  - Without this feature, `HAKO_TLV_SHIM=1` has no effect and the original path is used.

TLV shim diagnostics
- HAKO_TLV_SHIM_TRACE=0|1
  - When 1 (with `tlv-shim` feature), emit a concise trace tag `[tlv/shim:<Box>.<method>]` for shimmed calls.
  - Default: minimal noise（`MapBox.set` のみ）。詳細な対象はフィルタで拡張。
- HAKO_TLV_SHIM_FILTER=<CommaSeparatedList>
  - Filter which calls are traced（例: `MapBox.set,ArrayBox.push`）。`<Box>.<method>` または `method` のみで一致。
  - 未設定時は最小（`MapBox.set` のみ）。
- HAKO_TLV_SHIM_TRACE_DETAIL=0|1
  - When 1, emits `[tlv/shim:detail argc=N]`.

Examples (TLV trace)
- `HAKO_TLV_SHIM=1 HAKO_TLV_SHIM_TRACE=1 HAKO_TLV_SHIM_FILTER=ArrayBox.push`
- `HAKO_TLV_SHIM=1 HAKO_TLV_SHIM_TRACE=1 HAKO_TLV_SHIM_FILTER=MapBox.get`
 - `HAKO_TLV_SHIM=1 HAKO_TLV_SHIM_TRACE=1 HAKO_TLV_SHIM_FILTER=ArrayBox.push,MapBox.get` (複数指定)
 - `HAKO_SHOW_CALL_LOGS=1 HAKO_CALL_TRACE=1 HAKO_CALL_TRACE_FILTER=env.console.log`（テストランナーのフィルタ無効＋extern だけ観測）

Core Thinning I (Phase 22.2) — Plugin C wrapper (design hook)
- HAKO_PLUGIN_LOADER_C_WRAP=0|1
  - When 1, emits a design-stage tag `[cwrap:invoke:<Box>.<method>]` at the plugin invocation site and then proceeds with the normal path.
  - Default OFF; no behavior change.
- HAKO_PLUGIN_LOADER_C_WRAP_FILTER=<CommaSeparatedList>
  - Filter for cwrap tags（例: `MapBox.set,ArrayBox.push`）。`<Box>.<method>` または `method` のみで一致。

Core Thinning I (Phase 22.2) — C-core probe (design hook)
- HAKO_C_CORE_ENABLE=0|1
  - When 1, emits a tag `[c-core:invoke:<Box>.<method>]` and (when built with feature `c-core`) calls a thin C probe (`nyash-c-core`) before proceeding with the normal path.
  - Default OFF; behavior unchanged.
- HAKO_C_CORE_TARGETS=<CommaSeparatedList>
  - Targets to probe（例: `MapBox.set,ArrayBox.push`）。未設定時は `MapBox.set` のみ。
  - Build note: enable C-core with `cargo build --release -p nyash-rust --features c-core`.
  - Examples:
    - `HAKO_C_CORE_ENABLE=1 HAKO_C_CORE_TARGETS=ArrayBox.push`
    - `HAKO_C_CORE_ENABLE=1 HAKO_C_CORE_TARGETS=ArrayBox.len,ArrayBox.length`

Related toggles used by smokes/tools (for parity with runner/test wrappers):

Call/route unified trace (optional)
- HAKO_CALL_TRACE=0|1
  - When ON, emits `[call:<target>.<method>]` for both plugin calls and extern calls.
  - Default OFF; logs go to stderr.
- HAKO_CALL_TRACE_FILTER=<CommaSeparatedList>
  - Restrict `[call:]` logs to specific targets.
  - Matches `<target>.<method>` or bare `method`.
  - Examples:
    - `HAKO_CALL_TRACE_FILTER=MapBox.set` (method-only)
    - `HAKO_CALL_TRACE_FILTER=env.console.log,MapBox.set` (mix target+method)
- HAKO_SHOW_CALL_LOGS=0|1
  - When 1, test runner disables its default log filter so `[call:]` traces appear in output.
- NYASH_PARSER_STAGE3=1, HAKO_PARSER_STAGE3=1, NYASH_PARSER_ALLOW_SEMICOLON=1
- NYASH_ENTRY_ALLOW_TOPLEVEL_MAIN=1
- NYASH_DISABLE_NY_COMPILER=1, HAKO_DISABLE_NY_COMPILER=1

LLVM backend selector (builder wrapper)
- NYASH_LLVM_BACKEND=llvmlite|crate|native
  - Selects the backend used by `tools/ny_mir_builder.sh` for `--emit obj|exe`.
  - Default: `llvmlite` (Python harness `tools/llvmlite_harness.py`).
  - `crate`: uses `./target/release/ny-llvmc` (build with `cargo build -p nyash-llvm-compiler --release`).
  - `native`: reserved for future Hako-native builder.
  - Linking extras for `--emit exe`: pass via `HAKO_AOT_LDFLAGS` (e.g., `-static`), `ny-llvmc` consumes `--libs`.

Name mapping note (EXE link convenience)
- nyash.console.* は C リンク時にシンボル名 `nyash_console_*` に正規化される（ドット→アンダースコア）。
  - 例: `externcall nyash.console.log(i8*)` → C シンボル `nyash_console_log`。
  - 最小 C ランタイム（Phase 22.3）の `nyash-kernel-min-c` は `nyash_console_log(char*)` を提供（設計段階）。

Kernel Minimal C Runtime (Phase 22.3 — design)
- NYASH_KERNEL_C_MIN=0|1
  - Reserved toggle for enabling the minimal C runtime shims（design‑stage; defaults OFF）
  - Build: `cargo build --release -p nyash-kernel-min-c`（not linked by default）