Fix panic when using bang operator on numeric literal #8888
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When using `!3` (the bang/not operator on a numeric literal), the compiler would compile successfully but panic at runtime with "unreachable code". The issue was that the type checker allowed a flex var to have both `from_numeral` and `not` constraints without detecting the incompatibility. At runtime, the numeric literal would default to Dec, but Dec has no `not` method, causing the panic. The fix adds validation in checkFlexVarConstraintCompatibility to detect when a flex var with `from_numeral` constraint (indicating a numeric type) also has constraints that are incompatible with numeric types (specifically the `not` method which only exists on Bool). When this incompatibility is detected, a proper MISSING METHOD type error is reported at compile time. - Add isMethodIncompatibleWithNumeric to identify Bool-only methods - Add checkFlexVarConstraintCompatibility to validate constraint compatibility - Call the new check after type-checking expressions in checkExprRepl - Also check in checkDeferredStaticDispatchConstraints for the flex case - Add snapshot test bang_on_numeric_literal.md to verify the fix Fixes #8885 Co-Authored-By: Claude Opus 4.5 <noreply@anthropic.com>
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When using
!3(the bang/not operator on a numeric literal), the compiler would compile successfully but panic at runtime with "unreachable code". The issue was that the type checker allowed a flex var to have bothfrom_numeralandnotconstraints without detecting the incompatibility. At runtime, the numeric literal would default to Dec, but Dec has nonotmethod, causing the panic.The fix adds validation to detect when a flex var with
from_numeralconstraint (indicating a numeric type) also has constraints that are incompatible with numeric types (specifically thenotmethod which only exists on Bool). When this incompatibility is detected, a proper MISSING METHOD type error is reported at compile time.Fixes #8885
Co-authored by Claude Opus 4.5