dnscrypt-proxy/vendor/github.com/go-task/slim-sprig/list.go

465 lines
8.8 KiB
Go

package sprig
import (
"fmt"
"math"
"reflect"
"sort"
)
// Reflection is used in these functions so that slices and arrays of strings,
// ints, and other types not implementing []interface{} can be worked with.
// For example, this is useful if you need to work on the output of regexs.
func list(v ...interface{}) []interface{} {
return v
}
func push(list interface{}, v interface{}) []interface{} {
l, err := mustPush(list, v)
if err != nil {
panic(err)
}
return l
}
func mustPush(list interface{}, v interface{}) ([]interface{}, error) {
tp := reflect.TypeOf(list).Kind()
switch tp {
case reflect.Slice, reflect.Array:
l2 := reflect.ValueOf(list)
l := l2.Len()
nl := make([]interface{}, l)
for i := 0; i < l; i++ {
nl[i] = l2.Index(i).Interface()
}
return append(nl, v), nil
default:
return nil, fmt.Errorf("Cannot push on type %s", tp)
}
}
func prepend(list interface{}, v interface{}) []interface{} {
l, err := mustPrepend(list, v)
if err != nil {
panic(err)
}
return l
}
func mustPrepend(list interface{}, v interface{}) ([]interface{}, error) {
//return append([]interface{}{v}, list...)
tp := reflect.TypeOf(list).Kind()
switch tp {
case reflect.Slice, reflect.Array:
l2 := reflect.ValueOf(list)
l := l2.Len()
nl := make([]interface{}, l)
for i := 0; i < l; i++ {
nl[i] = l2.Index(i).Interface()
}
return append([]interface{}{v}, nl...), nil
default:
return nil, fmt.Errorf("Cannot prepend on type %s", tp)
}
}
func chunk(size int, list interface{}) [][]interface{} {
l, err := mustChunk(size, list)
if err != nil {
panic(err)
}
return l
}
func mustChunk(size int, list interface{}) ([][]interface{}, error) {
tp := reflect.TypeOf(list).Kind()
switch tp {
case reflect.Slice, reflect.Array:
l2 := reflect.ValueOf(list)
l := l2.Len()
cs := int(math.Floor(float64(l-1)/float64(size)) + 1)
nl := make([][]interface{}, cs)
for i := 0; i < cs; i++ {
clen := size
if i == cs-1 {
clen = int(math.Floor(math.Mod(float64(l), float64(size))))
if clen == 0 {
clen = size
}
}
nl[i] = make([]interface{}, clen)
for j := 0; j < clen; j++ {
ix := i*size + j
nl[i][j] = l2.Index(ix).Interface()
}
}
return nl, nil
default:
return nil, fmt.Errorf("Cannot chunk type %s", tp)
}
}
func last(list interface{}) interface{} {
l, err := mustLast(list)
if err != nil {
panic(err)
}
return l
}
func mustLast(list interface{}) (interface{}, error) {
tp := reflect.TypeOf(list).Kind()
switch tp {
case reflect.Slice, reflect.Array:
l2 := reflect.ValueOf(list)
l := l2.Len()
if l == 0 {
return nil, nil
}
return l2.Index(l - 1).Interface(), nil
default:
return nil, fmt.Errorf("Cannot find last on type %s", tp)
}
}
func first(list interface{}) interface{} {
l, err := mustFirst(list)
if err != nil {
panic(err)
}
return l
}
func mustFirst(list interface{}) (interface{}, error) {
tp := reflect.TypeOf(list).Kind()
switch tp {
case reflect.Slice, reflect.Array:
l2 := reflect.ValueOf(list)
l := l2.Len()
if l == 0 {
return nil, nil
}
return l2.Index(0).Interface(), nil
default:
return nil, fmt.Errorf("Cannot find first on type %s", tp)
}
}
func rest(list interface{}) []interface{} {
l, err := mustRest(list)
if err != nil {
panic(err)
}
return l
}
func mustRest(list interface{}) ([]interface{}, error) {
tp := reflect.TypeOf(list).Kind()
switch tp {
case reflect.Slice, reflect.Array:
l2 := reflect.ValueOf(list)
l := l2.Len()
if l == 0 {
return nil, nil
}
nl := make([]interface{}, l-1)
for i := 1; i < l; i++ {
nl[i-1] = l2.Index(i).Interface()
}
return nl, nil
default:
return nil, fmt.Errorf("Cannot find rest on type %s", tp)
}
}
func initial(list interface{}) []interface{} {
l, err := mustInitial(list)
if err != nil {
panic(err)
}
return l
}
func mustInitial(list interface{}) ([]interface{}, error) {
tp := reflect.TypeOf(list).Kind()
switch tp {
case reflect.Slice, reflect.Array:
l2 := reflect.ValueOf(list)
l := l2.Len()
if l == 0 {
return nil, nil
}
nl := make([]interface{}, l-1)
for i := 0; i < l-1; i++ {
nl[i] = l2.Index(i).Interface()
}
return nl, nil
default:
return nil, fmt.Errorf("Cannot find initial on type %s", tp)
}
}
func sortAlpha(list interface{}) []string {
k := reflect.Indirect(reflect.ValueOf(list)).Kind()
switch k {
case reflect.Slice, reflect.Array:
a := strslice(list)
s := sort.StringSlice(a)
s.Sort()
return s
}
return []string{strval(list)}
}
func reverse(v interface{}) []interface{} {
l, err := mustReverse(v)
if err != nil {
panic(err)
}
return l
}
func mustReverse(v interface{}) ([]interface{}, error) {
tp := reflect.TypeOf(v).Kind()
switch tp {
case reflect.Slice, reflect.Array:
l2 := reflect.ValueOf(v)
l := l2.Len()
// We do not sort in place because the incoming array should not be altered.
nl := make([]interface{}, l)
for i := 0; i < l; i++ {
nl[l-i-1] = l2.Index(i).Interface()
}
return nl, nil
default:
return nil, fmt.Errorf("Cannot find reverse on type %s", tp)
}
}
func compact(list interface{}) []interface{} {
l, err := mustCompact(list)
if err != nil {
panic(err)
}
return l
}
func mustCompact(list interface{}) ([]interface{}, error) {
tp := reflect.TypeOf(list).Kind()
switch tp {
case reflect.Slice, reflect.Array:
l2 := reflect.ValueOf(list)
l := l2.Len()
nl := []interface{}{}
var item interface{}
for i := 0; i < l; i++ {
item = l2.Index(i).Interface()
if !empty(item) {
nl = append(nl, item)
}
}
return nl, nil
default:
return nil, fmt.Errorf("Cannot compact on type %s", tp)
}
}
func uniq(list interface{}) []interface{} {
l, err := mustUniq(list)
if err != nil {
panic(err)
}
return l
}
func mustUniq(list interface{}) ([]interface{}, error) {
tp := reflect.TypeOf(list).Kind()
switch tp {
case reflect.Slice, reflect.Array:
l2 := reflect.ValueOf(list)
l := l2.Len()
dest := []interface{}{}
var item interface{}
for i := 0; i < l; i++ {
item = l2.Index(i).Interface()
if !inList(dest, item) {
dest = append(dest, item)
}
}
return dest, nil
default:
return nil, fmt.Errorf("Cannot find uniq on type %s", tp)
}
}
func inList(haystack []interface{}, needle interface{}) bool {
for _, h := range haystack {
if reflect.DeepEqual(needle, h) {
return true
}
}
return false
}
func without(list interface{}, omit ...interface{}) []interface{} {
l, err := mustWithout(list, omit...)
if err != nil {
panic(err)
}
return l
}
func mustWithout(list interface{}, omit ...interface{}) ([]interface{}, error) {
tp := reflect.TypeOf(list).Kind()
switch tp {
case reflect.Slice, reflect.Array:
l2 := reflect.ValueOf(list)
l := l2.Len()
res := []interface{}{}
var item interface{}
for i := 0; i < l; i++ {
item = l2.Index(i).Interface()
if !inList(omit, item) {
res = append(res, item)
}
}
return res, nil
default:
return nil, fmt.Errorf("Cannot find without on type %s", tp)
}
}
func has(needle interface{}, haystack interface{}) bool {
l, err := mustHas(needle, haystack)
if err != nil {
panic(err)
}
return l
}
func mustHas(needle interface{}, haystack interface{}) (bool, error) {
if haystack == nil {
return false, nil
}
tp := reflect.TypeOf(haystack).Kind()
switch tp {
case reflect.Slice, reflect.Array:
l2 := reflect.ValueOf(haystack)
var item interface{}
l := l2.Len()
for i := 0; i < l; i++ {
item = l2.Index(i).Interface()
if reflect.DeepEqual(needle, item) {
return true, nil
}
}
return false, nil
default:
return false, fmt.Errorf("Cannot find has on type %s", tp)
}
}
// $list := [1, 2, 3, 4, 5]
// slice $list -> list[0:5] = list[:]
// slice $list 0 3 -> list[0:3] = list[:3]
// slice $list 3 5 -> list[3:5]
// slice $list 3 -> list[3:5] = list[3:]
func slice(list interface{}, indices ...interface{}) interface{} {
l, err := mustSlice(list, indices...)
if err != nil {
panic(err)
}
return l
}
func mustSlice(list interface{}, indices ...interface{}) (interface{}, error) {
tp := reflect.TypeOf(list).Kind()
switch tp {
case reflect.Slice, reflect.Array:
l2 := reflect.ValueOf(list)
l := l2.Len()
if l == 0 {
return nil, nil
}
var start, end int
if len(indices) > 0 {
start = toInt(indices[0])
}
if len(indices) < 2 {
end = l
} else {
end = toInt(indices[1])
}
return l2.Slice(start, end).Interface(), nil
default:
return nil, fmt.Errorf("list should be type of slice or array but %s", tp)
}
}
func concat(lists ...interface{}) interface{} {
var res []interface{}
for _, list := range lists {
tp := reflect.TypeOf(list).Kind()
switch tp {
case reflect.Slice, reflect.Array:
l2 := reflect.ValueOf(list)
for i := 0; i < l2.Len(); i++ {
res = append(res, l2.Index(i).Interface())
}
default:
panic(fmt.Sprintf("Cannot concat type %s as list", tp))
}
}
return res
}