type sync.readOnly

8 uses

	sync (current package)
		map.go#L47: 	read atomic.Pointer[readOnly]
		map.go#L71: type readOnly struct {
		map.go#L110: func (m *Map) loadReadOnly() readOnly {
		map.go#L114: 	return readOnly{}
		map.go#L228: 			m.read.Store(&readOnly{m: read.m, amended: true})
		map.go#L363: 			m.read.Store(&readOnly{m: read.m, amended: true})
		map.go#L463: 			read = readOnly{m: m.dirty}
		map.go#L487: 	m.read.Store(&readOnly{m: m.dirty})