Tip #6 from the Basic debugging checklist: B::Deparse can shed some light: 

while (1) {
    $inline = $_;
    if (isOneOf($inline, @contexts)) {
        next;
    }
    else {
        print $_;
    }
}
close KNOWN_HOSTS;

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In reply to Re: Why is the error thrown from close(FH) when the error is the missing <> on while(FH)? by toolic
in thread Why is the error thrown from close(FH) when the error is the missing <> on while(FH)? by techgrrl

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