1// Define a data type
 2type User struct {
 3    Name     string
 4    Email    string
 5    Age      int
 6    Username string
 7    Tags     []string
 8}
 9
10// Create a new collection
11c := collection.New()
12
13// Add indexes with different options
14c.AddIndex("name", func(v any) string {
15    return v.(*User).Name
16}, UniqueIndex)
17
18c.AddIndex("email", func(v any) string {
19    return v.(*User).Email
20}, UniqueIndex|CaseInsensitiveIndex)
21
22c.AddIndex("age", func(v any) string {
23    return strconv.Itoa(v.(*User).Age)
24}, DefaultIndex)  // Non-unique index
25
26c.AddIndex("username", func(v any) string {
27    return v.(*User).Username
28}, UniqueIndex|SparseIndex)  // Allow empty usernames
29
30// For tags, we index all tags for the user
31c.AddIndex("tag", func(v any) []string {
32    return v.(*User).Tags
33}, DefaultIndex)  // Non-unique to allow multiple users with same tag
34
35// Store an object
36id := c.Set(&User{
37    Name:  "Alice",
38    Email: "[email protected]",
39    Age:   30,
40    Tags:  []string{"admin", "moderator"},  // User can have multiple tags
41})
42
43// Retrieve by any index
44entry := c.GetFirst("email", "[email protected]")
45adminUsers := c.GetAll("tag", "admin")      // Find all users with admin tag
46modUsers := c.GetAll("tag", "moderator")    // Find all users with moderator tag