Golang | Checking the byte of slice for specified regular expression

A regular expression is a sequence of characters which define a search pattern. Go language support regular expressions. A regular expression is used for parsing, filtering, validating, and extracting meaningful information from large text, like logs, the output generated from other programs, etc.
In Go regexp, you are allowed to check whether the given slice byte contains any match of the specified regular expression pattern with the help of Match() function. This function is defined under the regexp package, so for accessing this method you need to import the regexp package in your program.

Syntax:

func Match(p string, s []byte) (result bool, err error)

Here, p represents the pattern and s represents a slice of bytes. This function returns true if the pattern matched or return false if the pattern does not match. And also return an error if found.

Example 1:

// Go program to illustrate how to check
// the given regexp present in the given slice
package main

import (
    "fmt"
    "regexp"
)

// Main function
func main() {

    // Creating and initializing
    // slice of bytes
    // Using shorthand declaration
    s1 := []byte{'G', 'E', 'E', 'K', 'S', 'F', 'O',
                      'R', 'G', 'E', 'E', 'K', 'S'}

    s2 := []byte{'g', 'f', 'g'}

    // Pattern
    p1 := "G"
    p2 := "g"
    p3 := "^^"
    p4 := "@"

    // Matching pattern
    // Using Match() function
    res1, e := regexp.Match(p1, s1)
    fmt.Println("Result and Error is:", res1, e)

    res2, e := regexp.Match(p2, s1)
    fmt.Println("Result and Error is:", res2, e)

    res3, e := regexp.Match(p3, s1)
    fmt.Println("Result and Error is:", res3, e)

    res4, e := regexp.Match(p4, s1)
    fmt.Println("Result and Error is:", res4, e)

    res5, e := regexp.Match(p1, s2)
    fmt.Println("Result and Error is:", res5, e)

    res6, e := regexp.Match(p2, s2)
    fmt.Println("Result and Error is:", res6, e)

    res7, e := regexp.Match(p3, s2)
    fmt.Println("Result and Error is:", res7, e)

    res8, e := regexp.Match(p4, s2)
    fmt.Println("Result and Error is:", res8, e)

}

Output:

Result and Error is: true <nil>
Result and Error is: false <nil>
Result and Error is: true <nil>
Result and Error is: false <nil>
Result and Error is: false <nil>
Result and Error is: true <nil>
Result and Error is: true <nil>
Result and Error is: false <nil>

Example 2:

// Go program to illustrate how to check
// the given regexp present in the given slice
package main

import (
    "fmt"
    "regexp"
)

// Main function
func main() {

    // Matching pattern in the
    // given slice of bytes
    // Using Match() function
    res1, e := regexp.Match(`eks`, []byte(`GeeksforGeeks`))
    fmt.Println(res1, e)

    res2, e := regexp.Match(`BAN`, []byte(`Banana`))
    fmt.Println(res2, e)

    res3, e := regexp.Match(`123`, []byte(`GeeksforGeeks`))
    fmt.Println(res3, e)

    res4, e := regexp.Match(`e(ks`, []byte(`GeeksforGeeks`))
    fmt.Println(res4, e)

}

Output:

true <nil>
false <nil>
false <nil>
false error parsing regexp: missing closing ): `e(ks`