in reply to Re^2: Matching or masking specific characters in an array of strings
in thread Matching or masking specific characters in an array of strings
They're not talking about "masking away" characters from a given character set in a single string. They're talking about masking multiple strings together in order find out which characters those strings have in common. Hence:
southern - yourself ---------- -ou--e--
(where - (minus) is the masking operation.)
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