slices.Sort in Go lang

Posted on by user

The slices.Sort function in Go is used for sorting slices. It was introduced in Go 1.18 as part of the new generics features, providing a more straightforward and type-safe way to sort slices without needing to convert them to a specific type like sort.IntSlice or sort.StringSlice. Here are some examples demonstrating how to use slices.Sort:

1. Sorting a Slice of Integers

package main

import (
    "fmt"
    "golang.org/x/exp/slices"
)

func main() {
    numbers := []int{5, 3, 4, 1, 2}
    slices.Sort(numbers)
    fmt.Println(numbers) // Output: [1 2 3 4 5]
}

2. Sorting a Slice of Strings

package main

import (
    "fmt"
    "golang.org/x/exp/slices"
)

func main() {
    strings := []string{"banana", "apple", "cherry"}
    slices.Sort(strings)
    fmt.Println(strings) // Output: [apple banana cherry]
}

3. Sorting a Slice of Custom Structs

To sort a slice of custom structs, you need to provide a comparison function.

package main

import (
    "fmt"
    "golang.org/x/exp/slices"
)

type Person struct {
    Name string
    Age  int
}

func main() {
    people := []Person{
        {"Bob", 31},
        {"Alice", 22},
        {"John", 42},
    }

    // Sorting by Age
    slices.SortFunc(people, func(a, b Person) bool {
        return a.Age < b.Age
    })

    fmt.Println(people)
    // Output: [{Alice 22} {Bob 31} {John 42}]
}

4. Using a Custom Comparison Function for Integers

You can also use slices.SortFunc for basic types if you want to customize the sorting logic.

package main

import (
    "fmt"
    "golang.org/x/exp/slices"
)

func main() {
    numbers := []int{5, 3, 4, 1, 2}

    // Sort in descending order
    slices.SortFunc(numbers, func(a, b int) bool {
        return a > b
    })

    fmt.Println(numbers) // Output: [5 4 3 2 1]
}

Remember to import golang.org/x/exp/slices as the slices package is part of Go’s experimental packages and not included in the standard library. These examples demonstrate the ease and flexibility of using slices.Sort and slices.SortFunc for sorting slices in Go.

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