diff --git a/README.md b/README.md index 762d757..3f1da0b 100644 --- a/README.md +++ b/README.md @@ -420,7 +420,7 @@ func Union(slices ...interface{}) interface{} //Union creates a slice of unique func UpdateByIndex(slice interface{}, index int, value interface{}) (interface{}, error) //update the slice element at index. func Without(slice interface{}, values ...interface{}) interface{} //creates a slice excluding all given values func GroupBy(slice, function interface{}) (interface{}, interface{}) // groups slice into two categories -func Count(slice, function interface{}) int // Count iterates over elements of slice, returns a count of all matched elements +Count[T any](slice []T, fn func(index int, t T) bool) int // Count iterates over elements of slice, returns a count of all matched elements ``` #### 10. strutil is for processing string diff --git a/README_zh-CN.md b/README_zh-CN.md index e774ec1..14fd0c8 100644 --- a/README_zh-CN.md +++ b/README_zh-CN.md @@ -421,7 +421,7 @@ func Union(slices ...interface{}) interface{} //slice并集, 去重 func UpdateByIndex(slice interface{}, index int, value interface{}) (interface{}, error) //在切片中index位置更新value func Without(slice interface{}, values ...interface{}) interface{} //slice去除values func GroupBy(slice, function interface{}) (interface{}, interface{}) //根据函数function的逻辑分slice为两组slice -func Count(slice, function interface{}) int +Count[T any](slice []T, fn func(index int, t T) bool) int ``` #### 10. strutil字符串处理包 diff --git a/slice/slice.go b/slice/slice.go index 899a100..77671a4 100644 --- a/slice/slice.go +++ b/slice/slice.go @@ -123,24 +123,23 @@ func Filter[T any](slice []T, fn func(index int, t T) bool) []T { // Count iterates over elements of slice, returns a count of all matched elements // The function signature should be func(index int, value interface{}) bool . -func Count(slice, function interface{}) int { - sv := sliceValue(slice) - fn := functionValue(function) - - elemType := sv.Type().Elem() - if checkSliceCallbackFuncSignature(fn, elemType, reflect.ValueOf(true).Type()) { - panic("function param should be of type func(int, " + elemType.String() + ")" + reflect.ValueOf(true).Type().String()) +func Count[T any](slice []T, fn func(index int, t T) bool) int { + if fn == nil { + panic("fn is missing") + } + + if len(slice) == 0 { + return 0 } - var counter int - for i := 0; i < sv.Len(); i++ { - flag := fn.Call([]reflect.Value{reflect.ValueOf(i), sv.Index(i)})[0] - if flag.Bool() { - counter++ + var count int + for i, v := range slice { + if fn(i, v) { + count++ } } - return counter + return count } // GroupBy iterate over elements of the slice, each element will be group by criteria, returns two slices