Extract All Regular Expressions from String in Golang

Regular expressions, also known as regex or regexp, are a powerful tool for manipulating and searching text strings in programming languages. Golang provides excellent support for regular expressions with the use of the built-in regexp package. In this article, we will discuss how to extract all regular expressions from a given string in Golang.

Extracting All Regular Expressions from a String

To extract all regular expressions from a given string in Golang, we will use the FindAllString function from the regexp package. The FindAllString function returns a slice of all non-overlapping matches of the regular expression in the input string. Here's the basic syntax of the FindAllString function ?

func (re *Regexp) FindAllString(s string, n int) []string

Here, re is a pointer to a regular expression object, s is the input string, and n is the maximum number of matches to return. If n is negative, FindAllString returns all matches.

Example

Let's take a look at an example to understand how to extract all regular expressions from a string ?

package main

import (
   "fmt"
   "regexp"
)

func main() {
   str := "Hello 123 World 456"
   re := regexp.MustCompile(`\d+`)
   result := re.FindAllString(str, -1)
   fmt.Println(result)
}

Output

[123 456]

In the above code, we have defined a string str that contains some numbers, and we have created a regular expression that matches one or more digits using the \d+ pattern. We have then used the FindAllString function to extract all regular expressions that match this pattern from the string str. The result variable contains a slice of all the regular expressions that were found.

Conclusion

In this article, we have learned how to extract all regular expressions from a given string in Golang using the built-in regexp package. The FindAllString function is a powerful tool that allows us to extract all non-overlapping matches of a regular expression from an input string. By using this function, we can easily extract all regular expressions from a string and use them for further processing or analysis.