C64-dev/newLang/planning/claims/E00-S03.md

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story: E00-S03 owner: root status: done started: 2026-11-07 depends-on: [E00-S01]

E00-S03 Claim

Intended change

Resolve the remaining language-level questions that would otherwise force the lexer, code generator, or runtime-fault implementation to guess.

File area

• docs/decisions.md
• docs/language-spec.md
• docs/architecture.md
• character-literal coverage under tests/grammar/

Acceptance evidence

• Cast, character-literal, overflow, and runtime-fault behavior is accepted, deferred, or rejected.
• No version 1 production relies on undefined behavior.
• Decisions and fixtures agree.

Coordination notes

E00-S02 completed before character-literal fixture changes began. No active agent owns the grammar fixture area.

Work log

• Recorded D111-D116 as baseline decisions following implementation approval.
• Deferred interface-to-class down-casts and debug overflow traps.
• Chose single-quoted PETSCII character literals and added accepted/rejected grammar evidence.
• Required stable runtime fault codes plus a map-resolvable address.

Completion

• Tests run: powershell -NoProfile -ExecutionPolicy Bypass -File tests/grammar/validate.ps1
• Results: grammar fixtures ok: 7 accepted, 12 rejected
• Files changed: canonical decisions/spec/architecture, character-literal fixtures, grammar coverage matrix, and this claim
• Remaining risks: exact runtime fault payload and table capacities depend on the E01 memory-map probes