Diagnostics reference

Wist facade codes

Code	Stage / meaning
UTC-WIST-001	source-length preflight limit
UTC-WIST-002	external-parameter-count preflight limit
UTC-WIST-LEX-001	lexer failure
UTC-WIST-PARSE-001	parser failure
UTC-WIST-DIALECT-001	dialect composition failure
UTC-WIST-RESOLVE-001	type/member resolution failure
UTC-WIST-RESOLVE-002	ambiguous resolution
UTC-WIST-COMPILE-001	backend compilation failure
UTC-WIST-SSA-001	experimental SSA route failure
UTC-WIST-EXEC-001	execution failure
UTC-WIST-VALIDATE-001	validation failure not classified above
UTC-WIST-999	unexpected internal failure

WistDiagnostic exposes code, severity, stage, source span, message and hints. Expected formula failures should be consumed through Validate or TryCompile; do not parse exception text as an API.

Generic Language SDK planning codes

Family	Codes	Meaning
feature graph	UTL1001–UTL1003, UTL1203	missing feature, feature conflict/cycle, unsupported backend
Toolchain API	UTL1501	definition/package API incompatibility
contribution graph	UTL2001–UTL2006, UTL2010–UTL2014	missing/excluded contribution, dependency cycle, capability provider resolution, conflicts and ownership eligibility
slot ownership	UTL2101–UTL2103	multiple owners or invalid explicit replacement
typed routes and passes	UTL2201–UTL2204	no compatible route, pass cycle, backend owner ambiguity, unplaceable pass
runtime provider	UTL2301–UTL2304	missing/ambiguous provider, missing execution input, provider removed by override

Handling pattern

var result = compiler.Compile(definition);
foreach (var diagnostic in result.Diagnostics)
{
    Console.Error.WriteLine(
        $"[{diagnostic.Severity}] {diagnostic.Code} " +
        $"({diagnostic.Stage}): {diagnostic.Message}");
}

Codes identify a contract class. Messages and suggested actions may become more precise during alpha; avoid persisting full English message text as a compatibility key.