If I understood correctly, OP wanted to ignore everything but alphabetic ("string") characters, as opposed to numbers ("no") and special characters. So the regex would have to be $regex = join "[^a-zA-Z]*", split //, $string;

Though the more I look at the question, the more it looks like an XY problem

In reply to Re^2: Getting element of array with a match by Eily
in thread Getting element of array with a match by shyamasoni

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