A simple mask with a regexp javascript

simple-mask-pattern.js

const cnpj = [/\D/, /\D/, '.', /\D/, /\D/, /\D/, '.', /\D/, /\D/, /\D/, '/', /\D/, /\D/, /\D/, /\D/, '-', /\D/, /\D/];
const celphone = ['+', '5', '5', ' ', /\D/, /\D/, ' ', /\D/, ' ', /\D/, /\D/, /\D/, /\D/, /\D/, /\D/, /\D/, /\D/];
const cpf = [/\D/, /\D/, /\D/, '.', /\D/, /\D/, /\D/, '.', /\D/, /\D/, /\D/, '.', /\D/, /\D/];
const cep = [/\D/, /\D/, /\D/, /\D/, /\D/, '-', /\D/, /\D/, /\D/];

function mask(e, formater) {
    const result = [];
    const { target } = e;
    for (let i = 0; i < target.value.length; i++) {
      if (i >= formater.length) break;
      result[i] = typeof formater[i] !== 'string' 
        ? target.value[i].replace(formater[i], '')
        : formater[i];
    }
    e.target.value = result.join('');
}

input.addEventListener('input', (e) => mask(e, cnpj));