use strict;
$::PUNISHMENT = 'q[print"I will not throw paper airplanes in class.\n"
+;]';
$::PUNISHMENT =~ s{.*}{q(q[{local$_=).$&.q(.qq[{chop}$/=).$_.q(];{eval
+&&redo}}])}e for qw(CHALK ONTO BLACK BOARD); 
s!!$::PUNISHMENT!eee;
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Credit for the core idea to Abigail.