usage-patterns-and-examples

# Usage Patterns and Examples ## Usage Patterns and Examples ### Installation in Your Project ```bash go get -u github.com/Goldziher/go-utils ``` ### Common Usage Patterns #### Working with Slices (JavaScript-style) The `sliceutils` package provides familiar operations for developers coming from JavaScript: ```go import "github.com/Goldziher/go-utils/sliceutils" // Filter and Map (chainable pattern) numbers := []int{1, 2, 3, 4, 5, 6, 7, 8, 9, 10} filtered := sliceutils.Filter(numbers, func(val int, idx int, slice []int) bool { return val%2 == 0 }) // [2, 4, 6, 8, 10] doubled := sliceutils.Map(filtered, func(val int, idx int, slice []int) int { return val * 2 }) // [4, 8, 12, 16, 20] // Reduce for aggregation sum := sliceutils.Reduce(numbers, func(acc int, cur int, idx int, slice []int) int { return acc + cur }, 0) // 55 // Set operations a := []int{1, 2, 3, 4} b := []int{3, 4, 5, 6} union := sliceutils.Union(a, b) // [1, 2, 3, 4, 5, 6] intersection := sliceutils.Intersection(a, b) // [3, 4] difference := sliceutils.Difference(a, b) // [1, 2, 5, 6] ``` #### Working with Maps ```go import "github.com/Goldziher/go-utils/maputils" data := map[string]int{"a": 1, "b": 2, "c": 3} // Extract keys and values keys := maputils.Keys(data) // ["a", "b", "c"] values := maputils.Values(data) // [1, 2, 3] // Filter map entries filtered := maputils.Filter(data, func(key string, value int) bool { return value > 1 }) // {"b": 2, "c": 3} // Merge maps (right-to-left precedence) m1 := map[string]int{"a": 1, "b": 2} m2 := map[string]int{"b": 3, "c": 4} merged := maputils.Merge(m1, m2) // {"a": 1, "b": 3, "c": 4} ``` #### Working with Structs ```go import "github.com/Goldziher/go-utils/structutils" type User struct { Name string `json:"name"` Age int `json:"age"` Email string `json:"email"` } user := User{Name: "Alice", Age: 30, Email: "alice@example.com"} // Convert struct to map (respects struct tags) userMap := structutils.ToMap(user, "json") // {"name": "Alice", "age": 30, "email": "alice@example.com"} ``` #### URL Query String Building ```go import "github.com/Goldziher/go-utils/urlutils" // From map params := map[string]any{ "search": "golang", "page": 1, "tags": []string{"generics", "utils"}, } query := urlutils.QueryStringifyMap(params) // "page=1&search=golang&tags=generics&tags=utils" // From struct type QueryParams struct { Search string `qs:"q"` Page int `qs:"page"` Tags []string `qs:"tag"` } params := QueryParams{Search: "golang", Page: 1, Tags: []string{"generics", "utils"}} query := urlutils.QueryStringifyStruct(params, "qs") // "page=1&q=golang&tag=generics&tag=utils" ``` ### Type Safety with Generics All functions provide compile-time type safety: ```go // Compile error: type mismatch numbers := []int{1, 2, 3} result := sliceutils.Map(numbers, func(val int, idx int, slice []int) string { return strconv.Itoa(val) // Returns []string, not []int }) ```