Returns a new slice with all elements that pass the test implemented by the provided function.

Implement an appropriate function for each type.
Use make() to create an appropriate slice.
Use range to iterate over elements in the given collection, using append() to add them to the resulting slice based on the result of fn.
The functions can be tweaked to allow for an index to be passed to fn as a second argument, if desired.

代码实现

func FilterInt(arr []int, f func(int) bool) []int {
    arf := make([]int, 0)
    for _, v := range arr {
        if f(v) {
            arf = append(arf, v)
        }
    }
    return arf
}
func FilterFloat64(arr []float64, f func(float64) bool) []float64 {
    arf := make([]float64, 0)
    for _, v := range arr {
        if f(v) {
            arf = append(arf, v)
        }
    }
    return arf
}
func FilterBool(arr []bool, f func(bool) bool) []bool {
    arf := make([]bool, 0)
    for _, v := range arr {
        if f(v) {
            arf = append(arf, v)
        }
    }
    return arf
}
func FilterString(arr []string, f func(string) bool) []string {
    arf := make([]string, 0)
    for _, v := range arr {
        if f(v) {
            arf = append(arf, v)
        }
    }
    return arf
}

使用样例

intCheck := func(x int) bool { return x > 1 }
FilterInt([]int{0, 2}, intCheck) // [2]
float64Check := func(x float64) bool { return x > 0.5 }
FilterFloat64([]float64{0.0, 1.0}, float64Check) // [1.0]
boolCheck := func(x bool) bool { return x }
FilterBool([]bool{false, true}, boolCheck) // [true]
stringCheck := func(x string) bool { return len(x) > 1 }
FilterString([]string{"", "hi"}, stringCheck) // ["hi"]