const unixScheme … const unixAbstractScheme … type builder … func (b *builder) Build(target resolver.Target, cc resolver.ClientConn, _ resolver.BuildOptions) (resolver.Resolver, error) { … } func (b *builder) Scheme() string { … } func (b *builder) OverrideAuthority(resolver.Target) string { … } type nopResolver … func (*nopResolver) ResolveNow(resolver.ResolveNowOptions) { … } func (*nopResolver) Close() { … } func init() { … }