|
1
|
|
|
package internal |
|
2
|
|
|
|
|
3
|
|
|
import ( |
|
4
|
|
|
"reflect" |
|
5
|
|
|
|
|
6
|
|
|
"github.com/gotilty/gotil/internal/errs" |
|
7
|
|
|
) |
|
8
|
|
|
|
|
9
|
|
|
// FindBy iterates over elements of collection, returns an object of fist element predicate if returns true for. |
|
10
|
|
|
// data := []int64{-100, -5, 30, 100} |
|
11
|
|
|
// newData, _ := FindBy(data, func(val interface{}, i int) bool { |
|
12
|
|
|
// if val.(int64) == 30 { |
|
13
|
|
|
// return true |
|
14
|
|
|
// } else { |
|
15
|
|
|
// return false |
|
16
|
|
|
// } |
|
17
|
|
|
// }) |
|
18
|
|
|
// // Output: 30 |
|
19
|
|
|
func FindBy(a interface{}, f func(val interface{}, i int) bool) (interface{}, error) { |
|
20
|
|
|
return FindByFromIndex(a, f, 0) |
|
21
|
|
|
} |
|
22
|
|
|
|
|
23
|
|
|
// FindByFromIndex iterates over elements of collection, returns an object of fist element predicate if returns true for. |
|
24
|
|
|
// It works same as FindBy just from parameter provides to set start index of given slice or array. |
|
25
|
|
|
func FindByFromIndex(a interface{}, f func(val interface{}, i int) bool, from int) (interface{}, error) { |
|
26
|
|
|
val := reflect.ValueOf(a) |
|
27
|
|
|
switch val.Kind() { |
|
28
|
|
|
case reflect.Slice, reflect.Array: |
|
29
|
|
|
index := findIndex(val, f, 0) |
|
30
|
|
|
if index > -1 { |
|
31
|
|
|
return val.Index(index).Interface(), nil |
|
32
|
|
|
} |
|
33
|
|
|
return nil, nil |
|
34
|
|
|
} |
|
35
|
|
|
return nil, errs.NewUnsupportedTypeError(val.Kind().String()) |
|
36
|
|
|
} |
|
37
|
|
|
|
|
38
|
|
|
func findIndex(val reflect.Value, f func(val interface{}, i int) bool, from int) int { |
|
39
|
|
|
length := val.Len() |
|
40
|
|
|
if length == 0 { |
|
41
|
|
|
return -1 |
|
42
|
|
|
} |
|
43
|
|
|
index := 0 |
|
44
|
|
|
if from < 0 { |
|
45
|
|
|
index = max(length+index, 0) |
|
46
|
|
|
} else { |
|
47
|
|
|
index = min(index, length-1) |
|
48
|
|
|
} |
|
49
|
|
|
return baseFindIndex(val, f, index, false) |
|
50
|
|
|
} |
|
51
|
|
|
|