global

def decl
  case entry = env.constant_entry(full_name)
  when ::RBS::Environment::ConstantEntry
    entry.decl
  when ::RBS::Environment::ClassEntry, ::RBS::Environment::ModuleEntry
    entry.primary_decl
  when ::RBS::Environment::ClassAliasEntry, ::RBS::Environment::ModuleAliasEntry
    entry.decl
  else
    raise
  end
end