tomoaki
c117a04035
Root cause: toString/stringify/str were being rewritten to Global/Method calls with class inference, causing Main.toString/0 to be called for primitives. Fix (Box-First + Legacy Deletion): 1. ✅ MIR Builder - toString normalization (special.rs) - ALWAYS emit BoxCall with method_id=0 for toString/stringify/str - Do NOT rewrite to Global(Class.str/0) or Method calls - DELETED 70+ lines of complex class inference logic - Primitive guard with method name filter (known.rs) 2. ✅ JSON Serializer - method_id output (mir_json_emit.rs) - Include method_id field in BoxCall JSON for LLVM 3. ✅ LLVM Backend - universal slot #0 support - Extract method_id from JSON (instruction_lower.py) - Box primitives via nyash.box.from_i64 (boxcall.py) - Invoke toString via plugin system with method_id=0 - ⚠️ TODO: Add nyash.integer.tostring_h to kernel Test Results: ✅ VM: local x = 1; print(x.toString()) → "1" (PASS) ✅ VM: array_length test (boxed Integer) → PASS ⚠️ LLVM: Compiles successfully, needs kernel function SSOT: slot_registry - toString is ALWAYS universal slot #0 Legacy Deleted: - special.rs: Complex class inference rewrite (~70 lines) - special.rs: Unique suffix fallback for toString - special.rs: Main box special handling Files changed: - src/mir/builder/rewrite/special.rs (try_early_str_like_to_dst) - src/mir/builder/rewrite/known.rs (primitive guards x4) - src/runner/mir_json_emit.rs (method_id serialization x2) - src/llvm_py/builders/instruction_lower.py (method_id extraction) - src/llvm_py/instructions/boxcall.py (slot #0 handler) - docs/reference/language/quick-reference.md (toString SSOT) 🎊 Generated with Claude Code Co-Authored-By: Claude Sonnet 4.5 <noreply@anthropic.com>
123 lines
4.6 KiB
Markdown
123 lines
4.6 KiB
Markdown
# REPL Mode (Read–Eval–Print Loop) — Specification (SSOT)
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Status: Draft (design locked; implementation may lag)
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This document defines Nyash REPL mode semantics. The primary design goal is:
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- **File mode** stays strict and box-oriented (no mutable globals at top-level).
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- **REPL mode** is convenience-oriented (interactive, persistent session scope, implicit locals).
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- **Parser stays the same**; the difference is primarily **binding (name resolution)** rules.
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## Terms
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- **Top-level**: Code that is not inside a function/method body.
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- **File mode**: Normal execution of a `.hako`/Nyash file via the runner.
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- **REPL mode**: Interactive execution session (future CLI: `--repl`).
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- **Global variable (in this project)**: A mutable binding created at file top-level (e.g., `x = 1` or `local x = 1` at top-level).
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## 1) File Mode vs REPL Mode (high-level contract)
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### File mode (strict)
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- Top-level allows **declarations only** (e.g., `box`, `static box`, `function`, `static function`, `using`).
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- Top-level **statements are rejected** (Fail-Fast):
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- assignment (`x = 1`)
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- `local` declarations (`local x = 1`)
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- expression statements (`f()`), `print(...)`, control flow statements, etc.
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- Rationale: prevents mutable globals; keeps “state lives in boxes” discipline.
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### REPL mode (convenient)
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- The REPL has exactly one **persistent session scope**.
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- Session scope is conceptually a **lexical frame that persists across inputs**.
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- Assignments can create bindings implicitly (see §2).
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- Reads of undefined names are errors (Fail-Fast; no silent `void`).
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CLI entry (initial policy):
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- Start explicitly with `hakorune --repl` (optional short alias: `-i`).
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## 2) Binding Rules in REPL Mode
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### 2.1 Implicit local on assignment (key feature)
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When executing `name = expr` in REPL mode:
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- If `name` already exists in the session scope, update it.
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- If `name` does not exist, **create a new session binding** and assign to it.
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This applies to compound assignments as well (if supported): `name += expr`, etc.
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### 2.2 Reads are strict
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When evaluating `name` in REPL mode:
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- If `name` exists in the session scope, return its value.
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- Otherwise, raise **NameError / undeclared variable** (Fail-Fast).
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### 2.3 `local` is accepted but not required
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REPL accepts `local name = expr` / `local name` as explicit declarations.
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- Semantics: declare/update `name` in the session scope (same end result as implicit assignment).
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- Guidance: `local` remains useful for clarity, but REPL users are not forced to write it.
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## 3) Output Rules (REPL UX contract)
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REPL output distinguishes expressions vs statements:
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- If the input is an **expression**, print its value (pretty display) unless it is `void`.
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- If the input is a **statement**, do not auto-print.
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### 3.1 Convenience binding `_`
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- `_` is bound to the **last auto-printed value** (expressions only).
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- `_` is not updated when the value is `void`.
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### 3.2 Output suppression (planned)
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- A trailing `;` may suppress auto-print for expressions (planned; should be implemented without changing the core parser).
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## 4) REPL Meta Commands
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REPL supports dot-commands (not part of the language grammar):
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- `.help` — show help
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- `.exit` — exit the REPL
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- `.reset` — clear the session scope (remove all bindings and definitions created in the session)
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Additional commands may be added for debugging (e.g., `.ast`, `.mir`), but they must remain REPL-only and default-off for CI.
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## 5) Compatibility and `strip_local_decl` policy
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Historical compatibility code exists that can strip top-level `local` from certain inputs.
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SSOT policy:
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- **File mode must not “strip and accept” top-level `local`** (would violate the “no globals” rule).
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- If compatibility behavior is kept, it must be **REPL-only** and/or explicitly gated (e.g., `--compat`), with a stable warning tag.
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## 6) Error Messages (Fail-Fast wording)
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Recommended file-mode errors:
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- `Error: top-level statements are not allowed in file mode. Put code inside Main.main() or run with --repl.`
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- `Error: 'local' is not allowed at top-level in file mode. Use Main.main() or REPL mode.`
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## 7) Minimal Conformance Tests (spec lock)
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### File mode
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1. `x = 1` at top-level → error (top-level statements not allowed)
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2. `local x = 1` at top-level → error (local not allowed at top-level)
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3. `print("hi")` at top-level → error
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4. Declarations at top-level → OK
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5. Statements inside `Main.main()` or `main()` → OK
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### REPL mode
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1. `x = 1` then `x` → prints `1`
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2. `y` (undefined) → NameError
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3. `x = 1; x = 2; x` → prints `2`
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4. `local z = 3; z` → prints `3`
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5. `x = 1; .reset; x` → NameError
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