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Error And Diagnostic Codes

Vela diagnostics are structured by subsystem. The exact code list is still stabilizing, so this page groups the durable families rather than pretending a complete generated catalog exists.

Parser and semantic errors cover invalid syntax, unresolved names, duplicate declarations, invalid assignment targets, rejected generic type syntax, top-level side effects, and invalid module imports.

These errors should include source spans and related locations when available.

Runtime errors cover type guard failures, bad calls, arithmetic failures, budget exhaustion, stack depth limits, missing entries, and value conversion failures.

Host and reflection errors cover field not found, field not writable, permission denied, required capability missing, stale host ref generation, unknown reflected item, and reflect-call denial.

Hot reload diagnostics cover compile failures, ABI mismatches, schema incompatibilities, effect/access expansion, source graph problems, and rejected top-level side effects.

Reports should state that the previous active version remains current when an update is rejected.