使用\ b和国际字符的Javascript正则表达式问题

const regex = /[\b\p{L}]+/u;
const input = "This is a string with \ bletters and some Greek and Russian characters.";
const match = input.match(regex);

if (match) {
  console.log("The input contains at least one letter.");
  console.log("The match:", match[0]);
} else {
  console.log("The input does not contain any letters.");
}