zishuo/lo
1
0
Fork 0
mirror of https://github.com/samber/lo.git synced 2025-10-28 18:23:05 +08:00
Code Issues Packages Projects Releases Wiki Activity

parallel: remove mutex from Map and Times

Browse Source 
The slice is pre-allocated, a mutex is not needed.
This commit is contained in:
francisco souza
2022-03-05 17:44:59 -05:00
parent 094b6f974f
commit 25fe06d08e
1 changed files with 5 additions and 11 deletions
Download Patch File Download Diff File Expand all files Collapse all files

14
parallel/slice.go
View File

@@ -7,17 +7,14 @@ import "sync"
func Map[T any, R any](collection []T, iteratee func(T, int) R) []R { func Map[T any, R any](collection []T, iteratee func(T, int) R) []R {
result := make([]R, len(collection)) result := make([]R, len(collection))
var mu sync.Mutex
var wg sync.WaitGroup var wg sync.WaitGroup
wg.Add(len(collection)) wg.Add(len(collection))
for i, item := range collection { for i, item := range collection {
go func (_item T, _i int) { go func(_item T, _i int) {
res := iteratee(_item, _i) res := iteratee(_item, _i)
mu.Lock()
result[_i] = res result[_i] = res
mu.Unlock()
wg.Done() wg.Done()
}(item, i) }(item, i)
@@ -35,7 +32,7 @@ func ForEach[T any](collection []T, iteratee func(T, int)) {
wg.Add(len(collection)) wg.Add(len(collection))
for i, item := range collection { for i, item := range collection {
go func (_item T, _i int) { go func(_item T, _i int) {
iteratee(_item, _i) iteratee(_item, _i)
wg.Done() wg.Done()
}(item, i) }(item, i)
@@ -50,7 +47,6 @@ func ForEach[T any](collection []T, iteratee func(T, int)) {
func Times[T any](count int, iteratee func(int) T) []T { func Times[T any](count int, iteratee func(int) T) []T {
result := make([]T, count) result := make([]T, count)
var mu sync.Mutex
var wg sync.WaitGroup var wg sync.WaitGroup
wg.Add(count) wg.Add(count)
@@ -58,9 +54,7 @@ func Times[T any](count int, iteratee func(int) T) []T {
go func(_i int) { go func(_i int) {
item := iteratee(_i) item := iteratee(_i)
mu.Lock()
result[_i] = item result[_i] = item
mu.Unlock()
wg.Done() wg.Done()
}(i) }(i)
@@ -81,7 +75,7 @@ func GroupBy[T any, U comparable](collection []T, iteratee func(T) U) map[U][]T
wg.Add(len(collection)) wg.Add(len(collection))
for _, item := range collection { for _, item := range collection {
go func (_item T) { go func(_item T) {
key := iteratee(_item) key := iteratee(_item)
mu.Lock() mu.Lock()
@@ -106,7 +100,7 @@ func GroupBy[T any, U comparable](collection []T, iteratee func(T) U) map[U][]T
// determined by the order they occur in collection. The grouping is generated from the results // determined by the order they occur in collection. The grouping is generated from the results
// of running each element of collection through iteratee. // of running each element of collection through iteratee.
// `iteratee` is call in parallel. // `iteratee` is call in parallel.
func PartitionBy[T any, K comparable](collection []T, iteratee func (x T) K) [][]T { func PartitionBy[T any, K comparable](collection []T, iteratee func(x T) K) [][]T {
result := [][]T{} result := [][]T{}
seen := map[K]int{} seen := map[K]int{}