I am working my way through a beginning perl text book in my free time and I am currently reading the chapter on regular expressions. Anyways, I am confused by a piece of this code: 
$what = "[box]";
foreach (qw(in[box] out[box] white[sox])) {
if (/\Q$what\E/) {
print "$_ matched!\n";
}
}

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I get that it is storing the string \box\ in the varriable $what. If I understand it right, the foreach statement parses each of the strings in the parenthesies looking for the string \box\. What is the "qw" in the line "(qw(in\box\ out\box\ white\sox\))" though? I have no idea what that is. Sorry about the words box and sox being highlighted in red. I don't know how to stop this site from interpolating (correct word?) the brackets.

In reply to I don't understand a piece of this code by Socrates440

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