The regex of the OP will evaluate true for all strings except a string consisting of a single ';' character optionally followed by a newline because  $line !~ m{^;$} uses the  !~ negating binding operator.

Update: corrected per GrandFather's reply below.

In reply to Re^2: How to match a ; by AnomalousMonk
in thread How to match a ; by ewhitt

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