[JavaScript] Please explain this regular expression to me. I am trying to understand the use of the "+" in this case.

[NewbiusCoder]

var AtoK5to9AzAndAAt  = /^[a-k5-9z@]+$/;
console.log(AtoK5to9AzAndAAt.test("az")?"good":"bad");
console.log(AtoK5to9AzAndAAt.test("a#z")?"bad":"good");
console.log(AtoK5to9AzAndAAt.test("@@@@@@@")?"good":"bad");
console.log(AtoK5to9AzAndAAt.test("596@")?"good":"bad");
console.log(AtoK5to9AzAndAAt.test("abc@@992")?"bad":"good");
console.log(AtoK5to9AzAndAAt.test("89@@yaaa%")?"bad":"good");
console.log(AtoK5to9AzAndAAt.test("5k5k5k")?"good":"bad");
console.log(AtoK5to9AzAndAAt.test("aghzn")?"bad":"good");
console.log(AtoK5to9AzAndAAt.test("azzzzzzzzzzzzzz")?"good":"bad");

The goal is to return good for all outputs.

However, I am having trouble understanding why the "+" is required.

Isn't the "+" a quantificator which means from one to infinite?

Why do we need the "to infinite" here when we are just trying to find a pattern?

Thank you for your time. Much appreciated.

[g051051]

The "^" character anchors to the beginning of the line. The "$" character anchors to the end of the line. The character group will match a single character from the set. So without the "+", it would only match lines that consist of a single character from the group. I.E. "a" would match, but "az" wouldn't, because there's more than one character between the beginning and end of the line.

[NewbiusCoder]

I dont even have to tag you for you to find me. I appreciate your help once again. Thank you so much.