regexp.MatchString regexp.ReplaceAllString

`Regexp` digits

Suppose we want to remove all digits from a string in our Go program. This can be done with the regexp package, and the ReplaceAllString method.

In addition, the approach used to remove digits can be used to remove other characters within a range. We use a metacharacter in regexp.MustCompile to create the pattern.

Example

We introduce the RemoveDigits method, which receives a string and returns a modified string. In RemoveDigits, we call MustCompile to create a regexp.

Part 1 We have 3 example strings and call RemoveDigits on each of them, and print the output strings from RemoveDigits.

Part 2 In RemoveDigits, we must compile a regular expression with regexp.MustCompile. The "\d" indicates digit characters (0 through 9).

Part 3 We call ReplaceAllString on the regexp we just created. We replace matches within the string with an empty string, which removes them.

package main

import (
    "fmt"
    "regexp"
)

func RemoveDigits(input string) string {
    // Part 2: compile the regexp that matches digit characters.
    re := regexp.MustCompile(`\d`)

    // Part 3: use ReplaceAllString to replace all digits with an empty string.
    replacementResult := re.ReplaceAllString(input, "")
    return replacementResult;
}

func main() {
    // Part 1: call RemoveDigits on some example strings containing digits and print results.
    input1 := "Dot123Net456Perls"
    result1 := RemoveDigits(input1)
    fmt.Println(result1)

    input2 := "101Dalmatations"
    result2 := RemoveDigits(input2)
    fmt.Println(result2)

    input3 := "4 Score"
    result3 := RemoveDigits(input3)
    fmt.Println(result3)
}DotNetPerls
Dalmatations
 Score

Though it is possible to write rune-oriented methods that loop over characters, with regexp methods we often will require less code—and this often results in fewer bugs.

Regexp digits

Example

`Regexp` digits