The SemanticCallTag.Narrows built-ins with an ArgProp.Bounds parameter, whose result is one of
that argument's values (match.arg and its choices). Label a built-in Narrows with such a parameter
(in the DefaultBuiltinConfig or your own definitions) and it shows up here.
The SemanticCallTag.Narrows built-ins with an ArgProp.Bounds parameter, whose result is one of that argument's values (
match.argand itschoices). Label a built-inNarrowswith such a parameter (in the DefaultBuiltinConfig or your own definitions) and it shows up here.