hakorune/docs/guides/dev-local-alias.md

# Dev Sugar: @name = expr as local declaration

Status: dev-only, pre-expand sugar (no spec change)

Goal
- Speed up local declarations during development without impacting readability in shared code.

Syntax (dev sugar)
- Line-head only:
  - `@name = expr` → `local name = expr`
  - `@name: Type = expr` → `local name: Type = expr`

Rules
- Valid only at line start (leading spaces allowed). Inside expressions it is ignored.
- Declaration-only: not allowed for reassignments; use `name = expr` for assignments.
- Semantics are identical to `local` (scope/cleanup unchanged). Zero runtime cost.

Enablement
- Use the provided pre-expander script for dev: `tools/dev/at_local_preexpand.sh`.
- Example:
  - `tools/dev/at_local_preexpand.sh apps/tests/dev_sugar/at_local_basic.hako > /tmp/out.hako`
  - `NYASH_VM_USE_PY=1 ./target/release/hakorune --backend vm /tmp/out.hako`

Style
- Shared/committed code: prefer explicit `local` (nyfmt may normalize @ to `local`).
- Dev/repl/prototype: `@` is acceptable to reduce noise.

Notes
- This is a text pre-expansion; it does not change the parser or MIR.
- The pattern is conservative to avoid collisions with comments and inline usages.
selfhost(pyvm): MiniVmPrints – prefer JSON route early-return (ok==1) to avoid fallback loops; keep default behavior unchanged elsewhere 2025-09-22 07:54:25 +09:00			`# Dev Sugar: @name = expr as local declaration`

			`Status: dev-only, pre-expand sugar (no spec change)`

			`Goal`
			`- Speed up local declarations during development without impacting readability in shared code.`

			`Syntax (dev sugar)`
			`- Line-head only:`
			- `@name = expr` → `local name = expr`
			- `@name: Type = expr` → `local name: Type = expr`

			`Rules`
			`- Valid only at line start (leading spaces allowed). Inside expressions it is ignored.`
			- Declaration-only: not allowed for reassignments; use `name = expr` for assignments.
			- Semantics are identical to `local` (scope/cleanup unchanged). Zero runtime cost.

			`Enablement`
			- Use the provided pre-expander script for dev: `tools/dev/at_local_preexpand.sh`.
			`- Example:`
phase: 20.49 COMPLETE; 20.50 Flow+String minimal reps; 20.51 selfhost v0/v1 minimal (Option A/B); hv1-inline binop/unop/copy; docs + run_all + CURRENT_TASK -> 21.0 2025-11-06 15:41:52 +09:00			- `tools/dev/at_local_preexpand.sh apps/tests/dev_sugar/at_local_basic.hako > /tmp/out.hako`
feat(joinir): Phase 213-2 Step 2-2 & 2-3 Data structure extensions Extended PatternPipelineContext and CarrierUpdateInfo for Pattern 3 AST-based generalization. Changes: 1. PatternPipelineContext: - Added loop_condition: Option<ASTNode> - Added loop_body: Option<Vec<ASTNode>> - Added loop_update_summary: Option<LoopUpdateSummary> - Updated build_pattern_context() for Pattern 3 2. CarrierUpdateInfo: - Added then_expr: Option<ASTNode> - Added else_expr: Option<ASTNode> - Updated analyze_loop_updates() with None defaults Status: Phase 213-2 Steps 2-2 & 2-3 complete Next: Create Pattern3IfAnalyzer to extract if statement and populate update summary 2025-12-10 00:01:53 +09:00			- `NYASH_VM_USE_PY=1 ./target/release/hakorune --backend vm /tmp/out.hako`
selfhost(pyvm): MiniVmPrints – prefer JSON route early-return (ok==1) to avoid fallback loops; keep default behavior unchanged elsewhere 2025-09-22 07:54:25 +09:00
			`Style`
			- Shared/committed code: prefer explicit `local` (nyfmt may normalize @ to `local`).
			- Dev/repl/prototype: `@` is acceptable to reduce noise.

			`Notes`
			`- This is a text pre-expansion; it does not change the parser or MIR.`
			`- The pattern is conservative to avoid collisions with comments and inline usages.`