1// run
2
3// Copyright 2023 The Go Authors. All rights reserved.
4// Use of this source code is governed by a BSD-style
5// license that can be found in the LICENSE file.
6
7package main
8
9import (
10	"fmt"
11	"maps"
12)
13
14func main() {
15	m := map[string]struct{}{}
16
17	// Fill m up to the max for 4 buckets = 48 entries.
18	for i := 0; i < 48; i++ {
19		m[fmt.Sprintf("%d", i)] = struct{}{}
20	}
21
22	// Add a 49th entry, to start a grow to 8 buckets.
23	m["foo"] = struct{}{}
24
25	// Remove that 49th entry. m is still growing to 8 buckets,
26	// but a clone of m will only have 4 buckets because it
27	// only needs to fit 48 entries.
28	delete(m, "foo")
29
30	// Clone an 8-bucket map to a 4-bucket map.
31	_ = maps.Clone(m)
32}
33