You know, you could simply do: 
while (<>) {
    next if !/p/;
    next if !/e/;
    next if !/r/;
    next if !/l/;
    print;
}

[download]
or (if you don't mind using unless)... 
while (<>) {
    next unless /p/;
    next unless /e/;
    next unless /r/;
    next unless /l/;
    print;
}

[download]

In reply to Re: A Quick Regex Question by McDarren
in thread A Quick Regex Question by chinamox

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