Can you spot this bug in this line from YAML::Mo?

gistfile1.pl

# Why do people think this stuff is clever?
no warnings;my$M=__PACKAGE__.::;*{$M.Object::new}=sub{bless{@_[1..$#_]},$_[0]};
*{$M.import}=sub{import warnings;$^H|=1538;my($P,%e,%o)=caller.::;shift;
eval"no Mo::$_",&{$M.$_.::e}($P,\%e,\%o,\@_)for@_;return if$e{M};
%e=(extends,sub{eval"no $_[0]()";@{$P.ISA}=$_[0]},has,sub{my$n=shift;
my$m=sub{$#_?$_[0]{$n}=$_[1]:$_[0]{$n}};$m=$o{$_}->($m,$n,@_)for sort keys%o;
*{$P.$n}=$m},%e,);*{$P.$_}=$e{$_}for keys%e;@{$P.ISA}=$M.Object};
*{$M.'builder::e'}=sub{my($P,$e,$o)=@_;$o->{builder}=sub{my($m,$n,%a)=@_;
my$b=$a{builder}or return$m;sub{$#_?$m->(@_):!exists$_[0]{$n}?$_[0]{$n}=
$_[0]->$b:$m->(@_)}}};*{$M.'default::e'}=sub{my($P,$e,$o)=@_;$o->{default}
=sub{my($m,$n,%a)=@_;$a{default}or return$m;sub{$#_?$m->(@_):!exists$_[0]{$n}
?$_[0]{$n}=$a{default}->(@_):$m->(@_)}}};my$i=\&import;*{$M.import}=sub{(@_==2
and not $_[1])?pop@_:@_==1?push@_,grep!/import/,@f:();goto&$i};@f=qw[builder
default import];use strict;use warnings;