2025-09-22 07:54:25 +09:00
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# Dev Sugar: @name = expr as local declaration
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Status: dev-only, pre-expand sugar (no spec change)
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Goal
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- Speed up local declarations during development without impacting readability in shared code.
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Syntax (dev sugar)
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- Line-head only:
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- `@name = expr` → `local name = expr`
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- `@name: Type = expr` → `local name: Type = expr`
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Rules
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- Valid only at line start (leading spaces allowed). Inside expressions it is ignored.
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- Declaration-only: not allowed for reassignments; use `name = expr` for assignments.
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- Semantics are identical to `local` (scope/cleanup unchanged). Zero runtime cost.
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Enablement
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- Use the provided pre-expander script for dev: `tools/dev/at_local_preexpand.sh`.
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- Example:
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2025-11-06 15:41:52 +09:00
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- `tools/dev/at_local_preexpand.sh apps/tests/dev_sugar/at_local_basic.hako > /tmp/out.hako`
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- `NYASH_VM_USE_PY=1 ./target/release/nyash --backend vm /tmp/out.hako`
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2025-09-22 07:54:25 +09:00
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Style
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- Shared/committed code: prefer explicit `local` (nyfmt may normalize @ to `local`).
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- Dev/repl/prototype: `@` is acceptable to reduce noise.
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Notes
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- This is a text pre-expansion; it does not change the parser or MIR.
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- The pattern is conservative to avoid collisions with comments and inline usages.
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