International Phone (E.164)

const re = new RegExp("^\\+[1-9]\\d{1,14}$", "");
const input = "+14155552671";
const match = input.match(re);
console.log(match ? match[0] : null);

import re

pattern = re.compile(r"^\+[1-9]\d{1,14}$")
input_text = "+14155552671"
for m in pattern.finditer(input_text):
    print(m.group(0))

package main

import (
	"fmt"
	"regexp"
)

func main() {
	re := regexp.MustCompile(`^\+[1-9]\d{1,14}$`)
	input := `+14155552671`
	for _, match := range re.FindAllString(input, -1) {
		fmt.Println(match)
	}
}