So, a regex that actually matched "A line beginning and ending with zero or more letters in the set/class {a}" would be /^[a]*.*[a]$/s: The beginning of the string has to be followed by zero or more a's, followed by zero or more things in the middle of the string, followed by zero or more a's before the end of the string (or before a newline preceding the end). But with that "zero" in there instead of "one" or more, you are only requiring that the string have a beginning and an end, which is true of all strings.

In reply to Re: Regex Semantics by ysth
in thread Regex Semantics by cbro

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