[T] DiagnosticFormat

type DiagnosticFormat<T, C, M> = T[C][M] extends CallableMessage<infer A> ? object : Record<string, unknown>;

Requires a format map of named string substitutions when the selected message is a callable message template.

Type Parameters

Type Parameter	Default type
T extends object	-
C extends keyof T	-
M extends keyof T[C]	"default"