// Map is a concurrent map with amortized-constant-time loads, stores, and deletes.
// It is safe for multiple goroutines to call a Map's methods concurrently.
//
+// Map is designed to reduce cache contention in the Go standard library.
+// It is optimized for use in concurrent loops with keys that are stable
+// over time, and either few steady-state stores, or stores localized to
+// one goroutine per key.
+//
+// For use cases that do not share these attributes, it will likely have
+// comparable or worse performance and worse type safety than an ordinary
+// map paired with a read-write mutex.
+//
// The zero Map is valid and empty.
//
// A Map must not be copied after first use.