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ADP-004 — Unicode Identifier Policy

• Status: Approved & Implemented
• Deciders: Poppy Team
• Phase: Wave 1

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Context

Unicode identifiers with different normalization forms (NFC vs NFD) can render identically on screen while representing completely distinct byte sequences, enabling homograph attacks and elusive bugs.

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Decisions Taken

1. Aipo mandates Normalization Form C (NFC) as the canonical standard.
2. The Lexer rejects characters outside designated safe sets and automatically applies NFC normalization.
3. All string values constructed by the runtime respect valid UTF-8 boundaries and grapheme clusters.