bee/vendor/github.com/astaxie/beego/utils/slice.go

171 lines
4.1 KiB
Go

// Copyright 2014 beego Author. All Rights Reserved.
//
// Licensed under the Apache License, Version 2.0 (the "License");
// you may not use this file except in compliance with the License.
// You may obtain a copy of the License at
//
// http://www.apache.org/licenses/LICENSE-2.0
//
// Unless required by applicable law or agreed to in writing, software
// distributed under the License is distributed on an "AS IS" BASIS,
// WITHOUT WARRANTIES OR CONDITIONS OF ANY KIND, either express or implied.
// See the License for the specific language governing permissions and
// limitations under the License.
package utils
import (
"math/rand"
"time"
)
type reducetype func(interface{}) interface{}
type filtertype func(interface{}) bool
// InSlice checks given string in string slice or not.
func InSlice(v string, sl []string) bool {
for _, vv := range sl {
if vv == v {
return true
}
}
return false
}
// InSliceIface checks given interface in interface slice.
func InSliceIface(v interface{}, sl []interface{}) bool {
for _, vv := range sl {
if vv == v {
return true
}
}
return false
}
// SliceRandList generate an int slice from min to max.
func SliceRandList(min, max int) []int {
if max < min {
min, max = max, min
}
length := max - min + 1
t0 := time.Now()
rand.Seed(int64(t0.Nanosecond()))
list := rand.Perm(length)
for index := range list {
list[index] += min
}
return list
}
// SliceMerge merges interface slices to one slice.
func SliceMerge(slice1, slice2 []interface{}) (c []interface{}) {
c = append(slice1, slice2...)
return
}
// SliceReduce generates a new slice after parsing every value by reduce function
func SliceReduce(slice []interface{}, a reducetype) (dslice []interface{}) {
for _, v := range slice {
dslice = append(dslice, a(v))
}
return
}
// SliceRand returns random one from slice.
func SliceRand(a []interface{}) (b interface{}) {
randnum := rand.Intn(len(a))
b = a[randnum]
return
}
// SliceSum sums all values in int64 slice.
func SliceSum(intslice []int64) (sum int64) {
for _, v := range intslice {
sum += v
}
return
}
// SliceFilter generates a new slice after filter function.
func SliceFilter(slice []interface{}, a filtertype) (ftslice []interface{}) {
for _, v := range slice {
if a(v) {
ftslice = append(ftslice, v)
}
}
return
}
// SliceDiff returns diff slice of slice1 - slice2.
func SliceDiff(slice1, slice2 []interface{}) (diffslice []interface{}) {
for _, v := range slice1 {
if !InSliceIface(v, slice2) {
diffslice = append(diffslice, v)
}
}
return
}
// SliceIntersect returns slice that are present in all the slice1 and slice2.
func SliceIntersect(slice1, slice2 []interface{}) (diffslice []interface{}) {
for _, v := range slice1 {
if InSliceIface(v, slice2) {
diffslice = append(diffslice, v)
}
}
return
}
// SliceChunk separates one slice to some sized slice.
func SliceChunk(slice []interface{}, size int) (chunkslice [][]interface{}) {
if size >= len(slice) {
chunkslice = append(chunkslice, slice)
return
}
end := size
for i := 0; i <= (len(slice) - size); i += size {
chunkslice = append(chunkslice, slice[i:end])
end += size
}
return
}
// SliceRange generates a new slice from begin to end with step duration of int64 number.
func SliceRange(start, end, step int64) (intslice []int64) {
for i := start; i <= end; i += step {
intslice = append(intslice, i)
}
return
}
// SlicePad prepends size number of val into slice.
func SlicePad(slice []interface{}, size int, val interface{}) []interface{} {
if size <= len(slice) {
return slice
}
for i := 0; i < (size - len(slice)); i++ {
slice = append(slice, val)
}
return slice
}
// SliceUnique cleans repeated values in slice.
func SliceUnique(slice []interface{}) (uniqueslice []interface{}) {
for _, v := range slice {
if !InSliceIface(v, uniqueslice) {
uniqueslice = append(uniqueslice, v)
}
}
return
}
// SliceShuffle shuffles a slice.
func SliceShuffle(slice []interface{}) []interface{} {
for i := 0; i < len(slice); i++ {
a := rand.Intn(len(slice))
b := rand.Intn(len(slice))
slice[a], slice[b] = slice[b], slice[a]
}
return slice
}