Your code is fine. Both \Q and \ will escape @. 

$ perl -le'print q{@@} =~ m|\A\Q@@\E\z| ? "match" : "no match"'
match

$ perl -le'print q{@@} =~ m|\A\@\@\z| ? "match" : "no match"'
match

[download]

Are you sure your input is what you think it is?

Update: Turns out that \Q only helps insofar as @@ doesn't get interpolated to begin with.

In reply to Re: regular expression with @@/ by ikegami
in thread regular expression with @@/ by jim_neophyte

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