Splitting the slice after the specified separator in Golang

In Golang, there are multiple ways to split a slice after a specified separator. This can be achieved using built-in functions and methods. In this article, we will explore some of the common ways to split a slice in Golang.

Using strings.SplitAfter Function

The strings package in Golang provides a SplitAfter function, which splits a string or slice of bytes after the specified separator and returns the result as a slice of strings

Example

package main

import (
   "fmt"
   "strings"
)

func main() {
   slice := []string{"apple_", "banana_", "cherry_", "date_"}
   sep := "_"
   result := make([]string, 0)

   for _, s := range slice {
      result = append(result, strings.SplitAfter(s, sep)...)
   }

   fmt.Println(result)
}

Output

[apple_  banana_  cherry_  date_ ]

Using bytes.SplitAfter Function

The bytes package in Golang provides a SplitAfter function, which splits a slice of bytes after the specified separator and returns the result as a slice of slices of bytes.

Example

package main

import (
   "bytes"
   "fmt"
)

func main() {
   slice := [][]byte{{97, 112, 112, 108, 101, 95}, {98, 97, 110, 97, 110, 97, 95}, {99, 104, 101, 114, 114, 121, 95}, {100, 97, 116, 101, 95}}
   sep := []byte{'_'}
   result := make([][]byte, 0)

   for _, s := range slice {
      result = append(result, bytes.SplitAfter(s, sep)...)
   }
   fmt.Println(result)
}

Output

[[97 112 112 108 101 95] [] [98 97 110 97 110 97 95] [] [99 104 101 114 114 121 95] [] [100 97 116 101 95] []]

Using Custom Function

We can also write a custom function to split a slice after a specified separator.

Example

package main

import (
   "fmt"
   "strings"
)

func splitAfter(slice []string, sep string) []string {
   result := make([]string, 0)

   for _, s := range slice {
      index := 0
      for {
         i := strings.Index(s[index:], sep)
         if i == -1 {
            break
         }
         result = append(result, s[index:i+index+len(sep)])
         index = i + index + len(sep)
      }
      result = append(result, s[index:])
   }
   return result
}

func main() {
   slice := []string{"apple_", "banana_", "cherry_", "date_"}
   sep := "_"
   result := splitAfter(slice, sep)

   fmt.Println(result)
}

Output

[apple_ banana_ cherry_ date_]

Conclusion

In this article, we explored some of the common ways to split a slice after a specified separator in Golang. We used the built-in functions provided by the strings and bytes packages, as well as a custom function. Depending on the requirements and the type of slice, we can choose the appropriate method to split a slice in Golang.