var word="abcd";
var regstr=word[0]+Array(word.length-1).join(".")+word.slice(-1);
var reg3=new RegExp("^"+regstr+"$");
console.log(reg3)
Ответ:
/^a..d$/
JavaScript test | #JavaScript
JA JavaScript test @js_test · 9.67K subscribers var word="abcd";
var regstr=word[0]+Array(word.length-1).join(".")+word.slice(-1);
var reg3=new RegExp("^"+regstr+"$");
console.log(reg3)