72 lines
1.5 KiB
Go
72 lines
1.5 KiB
Go
package sliceutil
|
|
|
|
import (
|
|
"strings"
|
|
. "tinyrdm/backend/utils"
|
|
)
|
|
|
|
// Map map items to new array
|
|
func Map[S ~[]T, T any, R any](arr S, mappingFunc func(int) R) []R {
|
|
total := len(arr)
|
|
result := make([]R, total)
|
|
for i := 0; i < total; i++ {
|
|
result[i] = mappingFunc(i)
|
|
}
|
|
return result
|
|
}
|
|
|
|
// FilterMap filter and map items to new array
|
|
func FilterMap[S ~[]T, T any, R any](arr S, mappingFunc func(int) (R, bool)) []R {
|
|
total := len(arr)
|
|
result := make([]R, 0, total)
|
|
var filter bool
|
|
var mapItem R
|
|
for i := 0; i < total; i++ {
|
|
if mapItem, filter = mappingFunc(i); filter {
|
|
result = append(result, mapItem)
|
|
}
|
|
}
|
|
return result
|
|
}
|
|
|
|
// Join join any array to a single string by custom function
|
|
func Join[S ~[]T, T any](arr S, sep string, toStringFunc func(int) string) string {
|
|
total := len(arr)
|
|
if total <= 0 {
|
|
return ""
|
|
}
|
|
if total == 1 {
|
|
return toStringFunc(0)
|
|
}
|
|
|
|
sb := strings.Builder{}
|
|
for i := 0; i < total; i++ {
|
|
if i != 0 {
|
|
sb.WriteString(sep)
|
|
}
|
|
sb.WriteString(toStringFunc(i))
|
|
}
|
|
return sb.String()
|
|
}
|
|
|
|
// JoinString join string array to a single string
|
|
func JoinString(arr []string, sep string) string {
|
|
return Join(arr, sep, func(idx int) string {
|
|
return arr[idx]
|
|
})
|
|
}
|
|
|
|
// Unique filter unique item
|
|
func Unique[S ~[]T, T Hashable](arr S) S {
|
|
result := make(S, 0, len(arr))
|
|
uniKeys := map[T]struct{}{}
|
|
var exists bool
|
|
for _, item := range arr {
|
|
if _, exists = uniKeys[item]; !exists {
|
|
uniKeys[item] = struct{}{}
|
|
result = append(result, item)
|
|
}
|
|
}
|
|
return result
|
|
}
|