regex

Node.js

let input = 'foobar'
let replaced = input.replace(/foo(.*)/i, 'qux$1')
console.log(replaced)
let match = /o{2}/i.test(input)
console.log(match)
input = '111-222-333'
let matches = input.match(/([0-9]+)/gi)
console.log(matches)

Output

quxbar
true
[ '111', '222', '333' ]

Go

package main
import (
    "fmt"
    "regexp"
)
func main() {
    input := "foobar"
    re := regexp.MustCompile(`(?i)foo(.*)`)
    replaced := re.ReplaceAllString(input, "qux$1")
    fmt.Println(replaced)
    re = regexp.MustCompile(`(?i)o{2}`)
    match := re.Match([]byte(input))
    fmt.Println(match)
    input = "111-222-333"
    re = regexp.MustCompile(`(?i)([0-9]+)`)
    matches := re.FindAllString(input, -1)
    fmt.Println(matches)
}

Output

quxbar
true
[111 222 333]